RV Glossary

RV Glossary

120 AC/12 DC/LP-gas 

The power sources on which RV refrigerators operate; 120 AC is 120 volts of alternating current (the same as in houses); 12 DC is 12 volts of direct current (the same as in motor vehicles); LPgas is liquid petroleum gas, otherwise known as propane. Some RV refrigerators can operate on two of the three sources, others on all three.

Adjustable Ball Mount

An adjustable ball mount allows the ball to be raised, lowered and tilted in small increments to allow fine tuning of the spring bar setup and to compensate for tow vehicle "squat," which occurs after the trailer coupler is lowered onto the ball.

Airbag

In RV terms, a sort of shock absorber positioned at the forward and rear axles of a motorhome.

Airstreaming

Using an Airstream travel trailer as RV of preference. Towing an Airstream travel trailer.

Amp 

Amp is short for ampere, the electric current unit of measure. RV sites with electrical hookup will specify the maximum amps supported, which generally come in units of 20, 30, or 50 amps. The RV power connector must match the various plugs of the site amp rating.

Anode Rod

An anode rod, when used in a water heater, attracts corrosion causing products in the water. These products attack the anode rod instead of the metal tank itself. The anode rod should be inspected yearly and changed when it is reduced to about 1/4 of its original size. The rods are used in steel water heater tanks - an aluminum tank has an inner layer of anode metal to accomplish the same thing. Anode rods should not be installed in an aluminum tank!

Arctic Pack or Package

Also spelled Arctic Pac and Arctic Pak, an optional kit to insulate RVs for winter camping.
Articulation Point  A joint between two objects which allows movement. In the case of RVs, an articulation point is where two vehicles are coupled together by a ball or fifth wheel hitch. When a truck is pulling a travel trailer or fifth wheel, a single articulation point exists. If a boat is towed behind the trailer, then two articulation points exist.

Auxiliary battery

Extra battery to run 12-volt equipment.
Awning  A roof-like structure made of canvas or other artificial materials that extends from the RV body to provide shade. Awnings are generally placed over entrances. Some extend and stow manually while others are operated electrically.

Axle Ratio

The final drive gear ratio created by the relationship between the ring and pinion gears and the rotation of the driveshaft. In a 4.1:1 axle ratio, for example, the driveshaft will rotate 4.1 times for each rotation of the axle shaft (wheel).
Back In  A slot in an RV park with a single entrance, designed to be backed into with the RV.

Back-up monitor

Video camera mounted on rear of motorhome to assist the driver visually with backing up the motorhome, via a monitor mounted in the driver's compartment or in a central area of the cab where it can be viewed by the driver from the driver's seat. These monitors are usually left in the 'on' position to also assist the driver with the flow of traffic behind the motorhome and in watching a "towed" vehicle.

Ball Mount

The part of the hitch system that supports the hitch ball and connects it to the trailer coupler. Ball mounts are available in load-carrying and weight-distributing configurations.
Basement  The storage compartment of an RV under the main living area. Basements are generally found on motor homes and fifth wheel trailers.

Batwing Antenna 

TV antenna on the roof on an RV characterized by two horizontal elements. Batwing antennas are generally raised and rotated with a hand crank from inside the RV living compartment.
Black Tank  Holding tank connected to the toilet, designed to hold sewage until it can be dumped into a septic system.
Black Water  Waste water from the toilet; sewage. 

Blueboy/Blue-Boy

Term for portable waste holding tank, often this plastic tank comes in a bright shade of blue, hence the term.
Boondocking  Strictly speaking, boondocking is camping far away from civilization without any facilities such as water or electricity; roughing it. In a more general sense it has come to mean camping or parking anywhere without facilities, relying strictly on the comforts provided by the RV. Many RVers refer to spending the night in an interstate rest area, shopping center parking lot, or truck stop, as boondocking. 

Brake Actuator

A device mounted under the dash of a towing vehicle to control the braking system of the trailer. Most Brake Actuators are based on a time delay; the more time the tow vehicle brakes are applied the "harder" the trailer brakes are applied.

Brake Controller

An electronic control unit mounted inside the vehicle that allows electric trailer brakes to become activated in harmony with the braking of the tow vehicle. This device can be used to adjust trailer brake intensity, or to manually activate the trailer brakes.

Breakaway Switch

A safety device that activates the trailer brakes in the event the trailer becomes accidentally disconnected from the hitch while traveling. The switch is connected by a cable to the tow vehicle. Breakaway is detected when the switch cable is pulled out during vehicle separation.

BTU  British Thermal Unit

A measurement of heat that is the quantity required to raise the temperature of one pound of water 1 degree Fahrenheit. RV air-conditioners and furnaces are BTU-rated.

Bubble Loose

Term for defining a variety of conditions; such as when describing the level of RV sitting (example: my RV is 'off-level' a half bubble; referring to a 'bubble-leveler' tool). Can also be used to describe a delamination condition.
Bump-Out  See Slide

Bump Steer

A term used to describe a condition where the front axle feels to be rapidly bottoming out on the jounce bumpers and transferred back through the steering column and steering wheel.
There can be several different causes to the problem with different cures for each condition. Sometimes a simple fix such as shocks or a steering stabilizer; sometimes more detailed corrections are needed to address serious manufacturing oversights.

Bumper-Mount Hitch

This type of hitch is available in two configurations: A bracket with a ball mounted to the bumper or a ball is attached to the bumper (typically on pickup trucks). These hitches have very limited RV applications.

Bumper-Pull

Slang term regarding the hitch or towing method for a conventional travel trailer or popup; receiver and ball-mount type hitch.

Bunkhouse

An RV area containing bunk beds instead of regular beds.

Bumper Pull Trailer

See Travel Trailer

Bus Conversion

A passenger bus converted to an RV.

Cabcover

The part of a type C mini-motorhome that overlaps the top of the vehicle's cab, usually containing a sleeping or storage unit.
Cabover  This term can refer to one of two things: 1) a Class C motor home, or 2) the sleeping area which is over the cab in Class C motor homes and truck campers. For an example of each, see Class C Motor Home and Truck Camper.

Camber Wheel alignment

Camber is the number of degrees each wheel is off of vertical. Looking from the front, tops of wheels farther apart than bottoms means "positive camber". As the load pushes the front end down, or the springs get weak, camber would go from positive to none to negative (bottoms of wheels farther apart than tops).

Camper

Another term for an RV, especially smaller RVs that are towed behind or carried on top of light trucks. Truckers generally refer to all RVs as campers in their CB conversations.

Camper Shell

Removable unit to go over the bed of a pickup truck.

Camper Trailer

See Folding Trailer

Camper Van

See Class B

Caravan

A group of RVers traveling together with their various RVs. Large caravans often space RVs five minutes or so apart with CB radios used for communication between the various RVers. The end vehicle is sometimes called the "tail gunner" and is the occupants watch out for a caravan member that may have had road trouble in order to assist.

Cargo Weight

Cargo Weight is the actual weight of all items added to the Curb Weight of the vehicle or trailer. This includes personal cargo, optional equipment, and Tongue or King Pin Weight. 

Cassette Toilet

Toilet with a small holding tank that can be removed from outside the vehicle in order to empty it.

Castor  Wheel alignment

The steering wheel’s desire to return to center after you turn a corner.

CB  See CB Radio

CB Radio  Citizens Band radio is a general use, short distance, two-way radio primarily used by truckers. CB's are also helpful to RV drivers to call for help in an emergency and listen for driving conditions. Many CB's on the market today also have weather channels with alerting features.

CDL

See Commercial Driver License

Chassis

The frame of a vehicle or motor home including the engine, transmission, drive train, axles, and wheels. When referring to a van or truck, the chassis also includes the cab.

Chassis Battery

Battery in motorhome for operating 12-volt components of drivetrain. Gas engine vehicles generally have one chassis battery and diesels two. Also referred to as the starting battery.

Class A Motorhome

A motor home built on a stripped truck chassis where the driving compartment is an integral part of the RV interior. Class A motor homes look like busses. Models range from 24 to 40 feet long.

Class B Motorhome

A motor home created from a minivan. Most models have raised roofs, but otherwise the living space is constrained by the dimensions of the van. Also known as a camping van conversion, basic living accommodations inside are ideal for short vacations or weekend trips. Models usually range from 16 to 21 feet.

Class C Motorhome

A motor home built on a cut-away van or truck chassis, including the cab. It differs from the Class A Motorhome in that the Class C uses the cab designed for the chassis. A full-size bed in the cabover section allows for ample seating, galley and bathroom facilities in the coach. Also called a "mini-motorhome" or "mini." Lengths range from approximately 16 to 32 feet.

CMV

See Commercial Motor Vehicle

Coach

Another name for a motorhome.

Cockpit

The front of a motorized RV where the pilot (driver) and co-pilot (navigator) sit.

Commercial Driver License

License issued by states to drivers of commercial motor vehicles (CMV). Some states require special licensing or endorsements for large RVs, but a commercial driver license (CDL) is rarely required for non-commercial RVs.

Commercial Motor Vehicle

Federal Motor Carrier Safety Administration definition: A commercial motor vehicle is any self-propelled or towed motor vehicle used on a highway in interstate commerce to transport passengers or property when the vehicle: (1) has a gross vehicle weight rating (GVWR) or gross combination weight rating (GCWR) or a gross vehicle weight (GVW) or gross combination weight (GCW) of 4,536 kilograms (10,001 pounds) or more, whichever is greater; or (2) is designed or used to transport more than 8 passengers, including the driver, for compensation; or (3) is designed or used to transport more than 15 passengers, including the driver, whether or not it is used to transport passengers for compensation; or (4) is used in transporting material found by the Secretary of Transportation to be hazardous under 49 U.S.C. 5103 and transported in a quantity requiring placarding under regulations prescribed by the Secretary under 49 CFR, Subtitle B, Chapter I, Subchapter C.

Condensation

Condensation is a result of warm moisture laden air contacting the cold window glass. Keeping a roof vent open helps to reduce humidity levels. Those added roof vent covers help to prevent cold air from dropping down through the vent while still allowing moist air to escape. Using the roof vent fan when showering or the stove vent fan when cooking also helps prevent excess moisture buildup.

Conventional Trailer

See Travel Trailer

Conversion Van

See Class B Motorhome

Converter

An electrical device that converts alternating current (AC) to direct current (DC) used to charge the RV batteries and to operate 12-volt DC devices while plugged into an AC source. Most RVs with electrical hookups will have a converter, since many of the lights and some other accessories run on 12-volt DC.

Coupler

The part of a trailer A-frame that attaches to the hitch ball.

Crosswise

A piece of furniture arranged across the RV from side to side rather than front to rear.

Curb Weight

The weight of a basic RV unit without fresh or waste water in the holding tanks but with automotive fluids such as fuel, oil, and radiator coolant.

Curbside

The side of the RV that would be at the curb when parked.

Detonation

Also known as "knock" or "ping," this is a condition in which some of the unburned air/fuel in the combustion chamber explodes at the wrong time in the ignition cycle, increasing mechanical and thermal stress on the engine.

Diesel Puller

Term for front engine diesel motorhome.

Diesel Pusher

A motorhome with a rear diesel engine.

Dinette

A booth-like dining area. Table usually drops to convert unit into a bed at night.

Dinghy

A vehicle towed behind a motorhome, sometimes with two wheels on a special trailer called a tow dolly, but often with all four wheels on the ground.

DSI  Direct Spark Ignition

This term refers to the method of igniting the main burner on a propane fired appliance. The burner is lit with an electric spark and the flame is monitored by an electronic circuit board. This ignition system is used in refrigerators, furnaces and water heaters. There is now a version of stove tops that light the burners with a DSI ignition.

Domicile

One′s fixed and permanent legal residence. Among RVers this generally refers to the state of legal residence. Difference between domicile and residence, as explained by the State of New York Court of Appeals:  Residence means living in a particular locality, but domicile means living in that locality with intent to make it a fixed and permanent home. Residence simply requires bodily presence as an inhabitant in a given place, while domicile requires bodily presence in that place and also an intention to make it one′s domicile.

Dooley

See Dual Rear Wheels

DRW

See Dual Rear Wheels

Dry Camping

Camping in an RV without external water or sewer hookups. 

Dry Weight

Dry Weight is the actual weight of a vehicle or trailer containing standard equipment without fuel, fluids, cargo, passengers, or optional equipment. 

Dual Electrical System

RV equipped with lights, appliances which operate on 12-volt battery power when self-contained, and with a converter, on 110 AC current when in campgrounds or with an onboard generator.
Dual Rear Wheels  A truck having two wheels on each side of the rear axle for a total of four wheels.

Dually

See Dual Rear Wheels

Ducted AC

Is air conditioning supplied through a ducting system in the ceiling. This supplies cooling air at various vents located throughout the RV.

Ducted HEAT

Is warm air from the furnace supplied to various locations in the RV through a ducting system located in the floor (similar to house heating systems).

Dump station

Usually a concrete pad with an inlet opening connected to an underground sewage system at a campground or other facility for emptying gray and black water from the RV holding tanks.

DW

See Dry Weight

Engine Oil Cooler

A heat exchanger, similar to a small radiator, through which engine oil passes and is cooled by airflow.

Equalizing Hitch

A hitch that utilizes spring bars, which are placed under tension to distribute a portion of the trailer's hitch weight to the tow vehicle's front axle and the trailer's axles. The hitch is also known as a weight-distributing hitch.

ETG

See Exhaust Temperature Gauge

Exhaust Brake

A device installed on the engine which causes deceleration by restricting the exhaust gases. Exhaust brakes are used to supplement the service brakes of a vehicle and to increase stopping power. Especially useful to slow heavy loads down steep grades.
Exhaust Temperature Gauge  Gauge indicating engine exhaust gas temperature as measured by a probe inserted into the gas flow. Temperature is generally measured directly after the exhaust manifold or after the turbo. Useful in preventing engine overheating.

FHU

See Full Hookup

Fifth Wheel

A trailer and hitch configuration connected to the tow truck directly above the rear axle by way of a special fifth wheel hitch. This causes several feet of the connected trailer to hang over the tow truck, placing about 15 to 25% of the trailer’s weight on the rear axle of the truck. Commercial trucks and trailers use this hitch configuration. Also commonly spelled as 5th wheel. 

Final Drive Ratio

The reduction ratio found in the gear set, which is located farthest from the engine. This is the same as the axle ratio.

Fiver

Another name for a fifth wheel.

FMCA

Abbreviation for Family Motor Coach Association.

FMV

Abbreviation for Fair Market Value.

Folding Camper

See Folding Trailer

Folding Trailer

Small, light-weight trailer that folds or collapses into a low profile, suitable for towing behind light vehicles such as cars, SUVs, and mini pickup trucks.

Frame-Mount Hitch

Class II and higher hitches are designed to be bolted to the vehicle frame or cross members. This type of hitch may have a permanent ball mount, or may have a square-tube receiver into which a removable hitch bar or shank is installed.

Fresh Water Tank

Tank for holding fresh water for drinking, cooking, and bathing while not connected to a city water supply.

Full Hookup

Term for campground accommodations offering water, sewer/septic and electricity; also refers to an RV with the abilities to use 'full-hookups.'

Full-timing

Living in one's RV all year long. These RVers are known as full-timers.

FW

See Fifth Wheel

Galley

The kitchen in an RV.

Gas Pusher

Slang for rear gasoline engine mounted chassis on motorhome.

Gaucho Sofa/dinette

Bench that converts into a sleeping unit; a term less used now than formerly.

GAW

Gross Axle Weight (GAW) is the actual weight placed on a single axle. 

GAWR

Gross Axle Weight Rating is the manufacturer's rating for the maximum allowable weight that an axle is designed to carry. GAWR applies to tow vehicle, trailer, fifth-wheel and motorhome axles.

GCW

Gross Combination Weight (GCW) is the actual weight of the fully loaded tow vehicle plus the towed vehicle (trailer, car, boat, etc.), including all cargo, fluids, passengers, and optional equipment. 

GCWR

Gross Combination Weight Rating is the maximum allowable weight of the combination of tow vehicle and trailer/ fifth-wheel, or motorhome and dinghy. It includes the weight of the vehicle, trailer/fifth-wheel (or dinghy), cargo, passengers and a full load of fluids (fresh water, propane, fuel, etc.).

Gear Vendor

Brand name for an auxiliary transmission designed to give the driver control of the vehicle's gear ratio and being able to split gears for peak performance and at the same time have an overdrive.

Generator

An electrical device powered by gasoline or diesel fuel, and sometimes propane, for generating 120-volt AC power.

Genset

Abbreviation for generator set.

Gooseneck

A colloquial name for fifth-wheel travel trailers. A trailer and hitch configuration connected to the tow truck directly above the rear axle by way of a standard ball hitch in the truck bed and a vertical, slender arm on front of the trailer. Gooseneck hitching is common on horse and utility trailers, but rarely found on RV's. 

Gooseneck Adapter

A device that attaches to the fifth wheel trailer's king pin and extends down about two feet. It couples with a ball hitch mounted in the bed of a truck, enabling the fifth wheel to be towed like a gooseneck trailer. 

Gooseneck Extender

See Gooseneck Adapter

Grade

The degree of inclination of a road. A grade of 6% or higher is considered steep.

Gray Tank

Holding tank connected to the sinks and shower, designed to hold waste water until it can be dumped into a septic system.

Gray Water

Used water that drains from the kitchen and bathroom sinks and the shower into a holding tank, called a gray water holding tank, that is located under the main floor of the RV.

GTW

Gross Trailer Weight (GTW) is the same as Gross Vehicle Weight (GVW) when referring to a trailer.   GTWR Gross Trailer Weight Rating (GTWR) is the maximum allowable weight of a trailer, fully loaded with cargo and fluids.


GVW

Gross Vehicle Weight (GVW) is the actual weight of the fully loaded vehicle or trailer, including all cargo, fluids, passengers, and optional equipment, as measured by a scale. 

GVWR

Gross Vehicle Weight Rating (GVWR) is the total allowable weight of a vehicle, including passengers, cargo, fluids and hitch weight.

Half-ton

Truck rating originally conceived to indicate cargo carrying capacity of a half-ton (1,000 lbs). Today, tonnage rating is no longer an accurate indication of cargo carrying capacity—it is more of a relational indication among trucks in different categories. Common one-ton pickup truck models are the Chevrolet 1500, Dodge 1500, Ford F-150, and GMC 1500.

Hard-sided RV

Walls made of aluminum or other hard surface.

Hauler Back

Truck body installed on a chassis in place of a bed, designed to tow or haul various loads. Most hauler backs look like a typical car wrecker without the lift. Hauler backs intended for RV towing have a flat surface and a hitch installed above the rear axle. Common options added to hauler backs are storage compartments and tool boxes.

Heat Exchanger

A heat exchanger is a device that transfers heat from one source to another. For example, there is a heat exchanger in your furnace - the propane flame and combustion products are contained inside the heat exchanger that is sealed from the inside area. Inside air is blown over the surface of the exchanger, where it is warmed and the blown through the ducting system for room heating. The combustion gases are vented to the outside air.

Heat Strip

A heat strip is an electric heating element located in the air conditioning system with the warm air distributed by the air conditioner fan and ducting system. They are typically 1500 watt elements (about the same wattage as an electric hair dryer) and have limited function. Basically they "take the chill off."

Heavy Duty Truck

Commercial truck designed for heavy duty. Heavy trucks are suitable for towing the heaviest of trailers, though they are rarely used for RV towing. 

High Profile

A fifth-wheel trailer with a higher-than-normal front to allow more than 6 feet of standing room inside the raised area.

Hitch

The fastening unit that joins a movable vehicle to the vehicle that pulls it.

Hitch Weight

The amount of weight imposed on the hitch when the trailer/fifth-wheel is coupled. Sometimes referred to as conventional trailer "tongue weight." Hitch weight for a travel trailer can be 1015 percent of overall weight; fifth-wheel hitch weight is usually 18 to 20 percent of the overall weight.

Holding Tanks

Tanks that retain waste water when the RV unit is not connected to a sewer. The gray water tank holds waste water from the sinks and shower; the black water tank holds sewage from the toilet.
Honey Wagon  Euphemism for the sewage pumping truck. Honey wagons are used to empty RV holding tanks in places where full hookups and dump stations are not available.

House Battery

Battery or batteries in motorhome for operating the 12-volt system within the motorhome, separate from the chassis, used for operating the lights, appliances, and systems. House batteries can be 12-volt units tied in parallel or pairs of 6-volt batteries tied in series (to double the voltage). The term house battery is of more significance in motorhomes because they contain one or more other batteries for the operation of the engine, referred to as the chassis or starting batteries.

HP

Abbreviation for "horse power."

HR

Abbreviation for Holiday Rambler, a well-known RV manufacturer.

Hula Skirt

Term used for a type of dirt skirt accessory some RVers use on the back of their motorhome to aid in the protection from debris thrown from their rear wheels to the vehicles directly behind them or being towed behind them. This dirt skirt is usually the length of the rear bumper and resembles a 'short' version of a Hawaiian 'hula-skirt,' hence the term.

Inverter

A unit that changes 12-volt direct current to 110-volt alternating current to allow operation of computers, TV sets, and such when an RV is not hooked up to electricity. Typical DC sources are batteries and solar panels.
ISP  Abbreviation for Internet Service Provider.

Island Queen

A queen-sized bed with walking space on both sides.

Jackknife

A 90% angle obtained from turning/backing fifth wheel or travel trailer with tow vehicle. Jackknifing a short bed truck towing a fifth wheel without the use of a slider hitch or extended fifth wheel pin box can result in damage to the truck cab or breaking out the back window of the truck cab from the truck and fifth wheel "colliding."
Jake Brake  See Exhaust Brake

KOA

Kampgrounds of America, a franchise chain of RV parks in North America that offers camping facilities to vacationers and overnighters.
King Pin  The pin by which a fifth wheel trailer attaches to the truck. It slides into the fifth wheel hitch and locks in place.

King Pin Weight

King Pin Weight (also called Pin Weight) is the actual weight pressing down on the fifth wheel hitch by the trailer. The recommended amount of King Pin Weight is 15%-25% of the GTW. 

Laminat

A sandwich of structural frame members, wall paneling, insulation and exterior covering, adhesive-bonded under pressure and/or heat to form the RV's walls, floor and/or roof.

Landing Gears

See Leveling Jack

Landing Legs

See Leveling Jack

Leveling

Positioning the RV in camp so it will be level, using ramps (also called levelers) placed under the wheels, built-in scissors jacks, or power leveling jacks.

Leveling Jack

A jack lowered from the underside of trailers and motor homes for the purpose of leveling the vehicle. A leveling jack is designed to bear a significant portion of the RVs weight, even lifting it off the ground on certain models.

Light Duty Truck

Personal truck designed for light duty, typically rated at one ton and below. Light trucks are suitable for towing small to medium trailers. 

Limited-Slip Differential

A differential that is designed with a mechanism that limits the speed and torque differences between its two outputs, ensuring that torque is distributed to both drive wheels, even when one is on a slippery surface.

LP Gas Propane

Abbreviation for liquefied petroleum gas, which is a gas liquefied by compression, consisting of flammable hydrocarbons and obtained as a by-product from the refining of petroleum or natural gas. Also called bottled gas, LPG (liquid petroleum gas) and CPG (compressed petroleum gas).

LPG

Liquefied Petroleum Gas, commonly written as "LP gas." Two examples of LPG are propane and butane. LPG is heavier than air in gas form and about half the weight of water in liquid form.

Livability Packages

These are items to equip a motorhome for daily living, which may be rented at nominal cost from rental firm, rather than brought from home. Include bed linens, pillows and blankets, bath towels, pots and pans, kitchen utensils, cutlery.

MDT  See Medium Duty Truck

Medium Duty Truck  Commercial truck designed for medium duty, typically rated above one ton. Medium duty trucks are built with heavier frames, brakes, and transmission compared to light trucks

MH

Abbreviation for "motorhome."

Mini Motor Home

See Class C

Minnie Winnie

A brand model of Winnebago.

Motor Coach

Term for motorhome on "bus-type" chassis.

Motor Home

A motor vehicle built on a truck or bus chassis and designed to serve as self-contained living quarters for recreational travel. Also commonly spelled as motorhome.

MSRP

Manufacturer Suggested Retail Price.

NADA

Abbreviation for National Automotive Dealer's Association.

NCC 

Net Carrying Capacity is the maximum weight of all passengers (if applicable), personal belongings, food, fresh water, supplies -- derived by subtracting the UVW from the GVWR. NCC differs slightly from the more widely used "payload" term, by including full fresh water and propane tank weights.

Nonpotable Water

Water that is not suitable for human consumption.

One-ton

Truck rating originally conceived to indicate cargo carrying capacity of one-ton (2,000 lbs). Today, tonnage rating is no longer an accurate indication of cargo carrying capacity—it is more of a relational indication among trucks in different categories

Park Model

Type of RV that is usually designed for permanent parking but is shorter in length than a traditional mobile home. All the amenities of a mobile home but not built for recreational travel. It lacks holding tanks and dual-voltage appliances, requiring to be plugged into water, sewage, and electrical facilities. A park model is more of a small mobile home than a recreational vehicle, in appearance and function.

Part-timers

People who use their RV for longer than normal vacation time but less than one year.

Patio Mat

Carpet or woven mat for use on ground outside of RV. Used whether or not a concrete patio pad is available where camping.

Payload

Payload is a weight rating. It is the maximum weight that persons plus cargo should never exceed. 

Payload Capacity

The maximum allowable weight that can be placed in or on a vehicle, including cargo, passengers, fluids and fifth-wheel or conventional hitch loads.

Pilot

A pilot is a small standby flame that is used to light the main burner of a propane fired appliance when the thermostat calls for heat. Pilots can be used in furnaces, water heaters, refrigerators, ovens and stove tops.

Pitch-in

Term for a RV campground "get-together", usually means "pitching-in" a covered dish or casserole.

PO

Abbreviation for "pop-up" camper.

Pop-out

Term for room or area that 'pops-out' for additional living space in RV. This type of expanded living area was more common before the technology of slide-out rooms became popular and available.

Popup/Pop-Up

Folding camping trailer.

Porpoising

A term used to define an up and down motion with a RV.

Primitive Camping

Also known as "dry camping," boondocking. Camping without the modern convenience of fullhookup facilities of city/well water, sewer/septic and electricity. Primitive campers rely on 'onboard' systems for these conveniences; generator, batteries, stored water, etc.

Pressure Regulator

See Water Pressure Regulator

Propane LPG

liquefied petroleum gas, used in RVs for heating, cooking and refrigeration. Also called bottle gas, for manner in which it is sold and stored.

Puller Slang for front engine motorhome. Term most often used to refer to front mounted diesel engine motorhomes.

Pull-through A campsite that allows the driver to pull into the site to park, then pull out the other side when leaving, without ever having to back up.

Pusher Slang for rear engine motorhome. Term most often used to refer to diesel engine motorhomes.
Pyro  See Exhaust Temperature Gauge
Rear Differential  A set of gears found in the rear axle of vehicles, designed to distribute drive shaft power to the two wheels. It applies power to both wheels while allowing each to spin at different rates during cornering.
Rear End  See Rear Differential

Receiver The portion of a hitch that permits a hitch bar or shank to be inserted. The receiver may be either 11/2-, 15/8- or 2-inch square; the smallest being termed a mini-hitch.
Recreational Vehicle  Vehicle or trailer with living accommodations used for traveling and recreational activities.

Reefer Slang for "refrigerator." Refrigerators are often found in either a "two way" or "three way" operating mode. Two way: has a gas mode and an AC mode. Three way: has a gas mode, AC mode, and 12-volt DC mode. The coolant used in RV refrigeration is ammonia. The two most common manufacturers of RV refrigerators are Norcold and Dometic.

RGAW  Rear Gross Axle Weight (GAW) is the actual weight placed on the rear axle. 
RGAWR  Rear Gross Axle Weight Rating (RGAWR) is the maximum number that the GAW of the rear axle should never exceed.

RIG Term, many RVers call their units.
RV  See Recreational Vehicle 
RVCG  Abbreviation for the RV Consumer Group organization.

RVDA Abbreviation for Recreational Vehicle Dealer's Association.

RVIA Abbreviation for Recreational Vehicle Industry Association.

Road Wander Term used to describe a lack of ability to maintain the motorhome in a straight, forward travel without constant back and forth motion of the steering wheel.

Safety Chains
A set of chains that are attached to the trailer A-frame and must be connected to the tow vehicle while towing. Safety chains are intended to keep the trailer attached to the tow vehicle in the event of hitch failure, preventing the trailer from complete separation. They should be installed using an X-pattern, so the coupler is held off the road in the event of a separation.

Screen Room Term for screen enclosure that attaches to the exterior of a RV for a "bug free" outside sitting area. Some screen rooms have a canvas type roof for rain protection as well.

Self-contained An RV that needs no external connections to provide short-term cooking, bathing, and heating functions and could park overnight anywhere.

Shank Also called a hitch bar or stinger, the shank is a removable portion of the hitch system that carries the ball or adjustable ball mount, and slides into the receiver.

Shore Cord The external electrical cord that connects the vehicle to a campground electrical hookup.

Shore Power A boating term adopted by the RV community to mean an electrical power hookup supplied to the RV by a fixed, external source (not by a portable generator). A full hookup RV site has shore power.

Sideout A unit that slides open when the RV is parked to expand the living area.
Slide-In Truck Camper  See Truck Camper

Slide-in Term for a type of camper that mounts on a truck bed, because often this type of camper "slides-in" to the truck bed.

Slide-out Additional living space that "slides-out" either by hydraulics, electricity or manually, when the RV is setup for camping.

Slide  A compartment added to an RV to increase interior space. It slides into the body during travel and slides out when parked.

Slider Slang for slider-hitch.

Slider-hitch Referring to a sliding hitch used on short bed trucks for enabling them to tow fifth wheels, allowing them sufficient clearance to jack-knife the trailer.

Snowbird Term for someone in a northern climate that heads "south" in winter months. A person who moves from cold weather to warm in an RV, generally staying a season.

Soft-sides Telescoping side panels on an RV that can be raised or lowered, usually constructed of canvas or vinyl and mesh netting.
Solar Panel  Device containing an array of solar cells which convert sunlight to electricity. Typically mounted on the roof of RVs and used for charging the batteries.

Spring Bar Component parts of a weight-distributing hitch system, the spring bars are installed and tensioned in such a manner as to distribute a portion of the trailer's hitch weight to the front axle of the tow vehicle and to the axles of the trailer.
Sport Utility Trailer  See Toy Hauler
Stabilizing Jack  A jack inserted under or lowered from trailers and motor homes for the purpose of stabilizing the vehicle. A stabilizing jack is not designed to bear a significant portion of the RVs weight, only a small amount to reduce movement during occupancy. Stabilizing jacks are generally found toward the back of trailers, under the king pin of fifth wheels, and under some slides.
Starting Battery  See Chassis Battery

Stinger See Shank
Stinky Slinky  Slang for the sewer hose, constructed from a spiral wire covered with vinyl. One end attaches to the RV piping and the other into the local sewer dump facilities.

Streetside The part of the vehicle on the street side when parked.

Sway Fishtailing action of the trailer caused by external forces that set the trailer's mass into a lateral (side-to-side) motion. The trailer's wheels serve as the axis or pivot point. Also known as "yaw."

Sway Control Devices designed to damp the swaying action of a trailer, either through a friction system or a "cam action" system that slows and absorbs the pivotal articulating action between tow vehicle and trailer.
Tagalong Trailer  See Travel Trailer

Tail Swing Motorhomes built on chassis with short wheelbases and long overhangs behind the rear axle are susceptible to tail swing when turning sharply. As the motorhome moves in reverse or turns a corner, the extreme rear of the coach can move horizontally and strike objects nearby (typically road signs and walls). Drivers need to be aware of the amount of tail swing in order to prevent accidents.

Tailgunner The end RV or vehicle in a caravan.

Telescoping Compacting from front to back and/or top to bottom to make the living unit smaller for towing and storage.
Tent Camper  See Folding Trailer
Tent Trailer  See Folding Trailer

Thermocouple
A thermocouple is a device that monitors the pilot flame of a pilot model propane appliance. If the pilot flame is extinguished the thermocouple causes the gas valve to shut off the flow of gas to both the pilot flame and the main burner.
Three Quarter Ton  Truck rating originally conceived to indicate cargo carrying capacity of three quarter tons (1,500 lbs). Today, tonnage rating is no longer an accurate indication of cargo carrying capacity—it is more of a relational indication among trucks in different categories. 

Three-way refrigerators - Appliances that can operate on a 12-volt battery, propane, or 110volt electrical power.
Toad  A vehicle towed behind the RV. That which was "towed.".

Toe Wheel alignment - Toe is the measure of whether the front of the wheels (looking down from the top) are closer (toe-in) or farther (toe-out) than the back of the wheels.
Tongue Jack  A jack lowered from the frame of a travel trailer, directly behind the tongue, for the purpose of leveling the trailer. A tongue jack is designed to bear a significant portion of the trailer’s weight, called the Tongue Weight (10% - 15% recommended).
Tongue Load  See Tongue Weight

Tongue Weight Tongue Weight (also called Tongue Load) is the actual weight pressing down on the hitch ball by the trailer. The recommended amount of Tongue Weight is 10%-15% of the GTW. 

Tow Bar A device used for connecting a dinghy vehicle to the motorhome when it's towed with all four wheels on the ground.

Tow Rating The manufacturer's rating of the maximum weight limit that can safely be towed by a particular vehicle. Tow ratings are related to overall trailer weight, not trailer size, in most cases. However, some tow ratings impose limits as to frontal area of the trailer and overall length. The vehicle manufacturer according to several criteria, including engine size, transmission, axle ratio, brakes, chassis, cooling systems and other special equipment, determines tow ratings.
Towcar A car towed by an RV to be used as transportation when the RV is parked in a campground.

Toy-hauler Term for fifth wheel, travel trailer or motorhome with built-in interior cargo space for motorcycles, bikes, etc.

Toy Hauler 

Photo courtesy of Jayco The term toy hauler is applied to both fifth wheels and travel trailers, and it describes an RV designed to carry toys—small cars, dune buggies, four wheelers, motorcycles, etc. Distinguishing features of a toy hauler is the large door in the back which opens down to create a ramp, dedicated garage area or fold-away furniture in the main living compartment, and often a third axle to support the heavy toys.

Trailer Brakes Brakes that are built into the trailer axle systems and are activated either by electric impulse or by a surge mechanism. The overwhelming majority of RVs utilize electric trailer brakes that are actuated when the tow vehicle's brakes are operated, or when a brake controller is manually activated. Surge brakes utilize a mechanism that is positioned at the coupler, that detects when the tow vehicle is slowing or stopping, and activates the trailer brakes via a hydraulic system (typically used on boats).

Transmission Cooler A heat exchanger similar to a small radiator through which automatic transmission fluid passes and is cooled by airflow.

Travel Trailer Also referred to as "conventional trailers," these types of rigs have an A-frame and coupler and are attached to a ball mount on the tow vehicle. Travel trailers are available with one, two or three axles. Depending upon tow ratings, conventional trailers can be towed by trucks, cars or sport-utility vehicles.

Travel Trailer 

Photo courtesy of Travelaire A towable trailer that hitches onto a ball mount on the tow vehicle and designed as living quarters for recreational travel. 

Triple towing Term for three vehicles attached together. Usually a tow vehicle pulling a fifth wheel and the fifth wheel pulling a boat.
Truck Camper 

Photo courtesy of Lance Camper Mfg. Corp. Living quarters designed to slide into the bed of a truck. The camper is fastened to the truck frame during transport and slides out onto its own legs at the camp site. 
TT  See Travel Trailer

TV  Abbreviation for "tow vehicle."

Umbilical Cord The wiring harness that connects the tow vehicle to the trailer, supplying electricity to the trailer's clearance and brake lights, electric brakes and a 12-volt DC power line to charge the trailer's batteries. An umbilical cord can also be the power cable that is used to connect to campground 120-volt AC electrical hookups.

Underbelly
The RV's underfloor surface, which is protected by a weatherproofed material.

UTQGL  Uniform Tire Quality Grade Labeling is a program that is directed by the government to provide consumers with information about three characteristics of the tire: tread wear, traction and temperature. Following government prescribed test procedures, tire manufacturers perform their own evaluations for these characteristics. Each manufacturer then labels the tire, according to grade.

UVW Unloaded Vehicle Weight is the weight of the vehicle without manufacturer's or dealer-installed options and before adding fuel, water or supplies.

Van Camper  See Class B

Wagon Master A leader, either hired or chosen, who guides a caravan of recreational vehicles on a trip. The Wagon Master usually makes advance reservations for campgrounds, shows, cruises, sightseeing and group meals.

Wally World Slang term used by RVers to describe a Wal-Mart.
Water Pressure Regulator  Device installed on water hose attached to city water to limit the water pressure entering the RV. Most regulators limit water pressure to 40 psi.

Weekenders People who own their RVs for weekend and vacation use.

Weight-Carrying Hitch Also known as a "dead-weight" hitch, this category includes any system that accepts the entire hitch weight of the trailer. In the strictest sense, even a weight-distributing hitch can act as a load-carrying hitch if the spring bars are not installed and placed under tension.

Weight-Distributing Hitch Also known as an "equalizing" hitch, this category includes hitch systems that utilize spring bars that can be placed under tension to distribute a portion of the trailer's hitch weight to the tow vehicle's front axle and the trailer's axles.

Weights
GAWR: Gross Axle Weight Rating. The maximum allowable weight each axle is designed to carry, as measured at the tires, therefore including the weight of the axle assembly itself. GAWR is established by considering the ratio of each of its components (tires, wheels, springs, and axle) and rating the axle on its weakest link. The GAWR assumes that the load is equal on each side. 

GCWR: Gross Combined Weight Rating. The maximum allowable combined weight of the tow vehicle and the attached towed vehicle. GCWR assumes both vehicles have functioning brakes, with exceptions in some cases for very light towed vehicles, normally less than 1,500 pounds. (check your chassis manual or towing guide). 

GVWR: Gross Vehicle Weight Rating. The maximum allowable weight of the fully loaded vehicle, including liquids, passengers, cargo, and tongue weight of any towed vehicle. 

NCC: Net Carrying Capacity. The maximum weight of all personal belongings, occupants, food, fresh water, LP gas, tools, dealer installed accessories, etc., that can be carried by the RV. (Technically, the GVWR less the UVW equals the NCC.) Payload Capacity. The maximum allowed weight that can be in or on a vehicle, including all cargo and accessories, fuel freshwater, propane, passengers and hitch loads. 

UVW: Unloaded Vehicle Weight. The weight of a vehicle as built at the factory with full fuel, engine (generator) oil and coolants. It does not include cargo, fresh water, LP gas, occupants, or dealer installed accessories. water (weight): 8.3 lbs. per gallon LP gas (weight): 4.5 lbs. per gallon driver (estimated weight): 200 lbs. passenger (estimated weight): 120 lbs. Gasoline: weighs 6.3 pounds per gallon Diesel fuel: weighs 6.6 pounds per gallon Propane: weighs 4.25 pounds per gallon

Wet Weight Term used by RVers to describe the weight of a RV with all storage and holding tanks full. i.e., water, propane, etc.

Wheelbase Distance between the center of the front and rear wheels of a vehicle, usually expressed in inches. If a motorhome includes a tag axle, the distance is measured from the front axle to the center point between the drive and tag axles.

Widebody Designs that stretch RVs from the traditional 96-inch width to 100 or 102 inches.
WiFi  See Wireless Internet

Winnie
Nickname for Winnebago, a well-known RV manufacturer.

Winterize To prepare the RV for winter use or storage, introducing non-toxic antifreeze into the water lines of an RV to prevent freezing and line breaks.
Wireless Internet  Technology that enables computers equipped with wireless network cards (also called WiFi) to connect to the Internet without requiring wired connections such as phone lines or cables. This service generally requires an additional fee and a sing-up process.
Work Camper  A person living in an RV and working. Many spell it as workamper after the web site and service by that name.
Workamper  See Work Camper

Yaw Fishtailing action of the trailer caused by external forces that set the trailer's mass into a lateral (side-to-side) motion. The trailer's wheels serve as the axis or pivot point. Also known as "sway."