Rail terminology: Meaning (information, definition, explanation, facts)

Rail terminology is a form of technical terminology. The difference between the mainly American term "railroad" and the mainly British term "railway" is the most obvious trans-Atlantic difference in rail terminology. (see usage of the terms railroad and railway for more information). There are also several others, caused by the parallel development of rail transport systems on both sides of the Atlantic. Various terms here are presented alphabetically, where a term has multiple names this is indicated. The note "US" indicates a term originating on the American continent, while "UK" refers to terms originating in the British Isles/Europe.

0-9

Note: for 4-4-0, 2-6-4T, 0-4-4-0, etc. see wheel arrangement

• 10 wheeler (US): locomotive with a 4-6-0 wheel arrangement

• American: locomotive with a 4-4-0 wheel arrangement
• Atlantic: locomotive with a 4-4-2 wheel arrangement

• B unit (US): a cabless booster locomotive, controlled via MU from a cab-equipped lead unit.
• ballast (UK): aggregate stone, gravel or cinders forming the track-bed on which sleepers (ties) and track is laid, for proper drainage
• bay platform: a type of platform/track arrangement where the train pulls into a siding, or dead-end, when serving the platform.
• bogie (UK): truck (US)
• boiler
• booster (US): (steam locomotive) An extra set of cylinders that can be engaged to drive a trailing truck or tender truck to give additional tractive effort at starting and low speeds; (diesel locomotive) a cabless B unit
• boxcar (US): van (UK)
• brake van (UK): caboose (US), cabin car (PRR only)

• caboose (US): brake van (UK)
• cant: angle. Can be used in the context of the cant of the rail track (the relative level one rail with another); and the cant of a rail, being the angle of that single rail relative to the perpendicular.
• railroad car, or rolling stock in British English, is a vehicle that is not a locomotive.
• cess (UK): a narrow strip of land (usually with cables and often with a walkway) between the edge of the outermost track and the start of non-railway land. Shortened from access.
• chimney (UK): smokestack or stack (US).
• compound engine: An articulated steam locomotive passing the output steam through two engines. One engine used high-pressure steam and passed the "low-pressure" steam on to the second. Attributed to Anatole Mallet.
• conductor (US): guard (UK).
• cylinder.

• diesel multiple unit or DMU: a set of diesel-powered self-propelling passenger rail vehicles usually able to operate in multiple with other such sets. Such units, especially those consisting of a single vehicle, are sometimes termed railcars.
• driver (UK): Engineer (US)
• driving van trailer or DVT: a special end carriage from which the train can be driven in reverse for push-pull operation.

• electric multiple unit or EMU: a set of electrically powered self-propelling passenger rail vehicles usually able to operate in multiple with other such sets
• engineer (US): driver, engine driver, train driver (UK)

• Fairlie: type of articulated locomotive
• feedwater heater: A device to preheat the water for a steam locomotive; improves efficiency.
• fettle, fettling: making repairs to rail track, especially concerned with maintaining the drainage of the ballast, and the proper cant of the rail track and rails.
• firebox
• four foot the part of the line between a pair of running rails. An abbreviation of four foot, eight-and-a-half-inches. See also six foot and ten foot.
• Free-mo: type of modular layout in model railroading
• funnel (this is a Thomas the Tank Engine misnomer, for a chimney (UK), smokestack (US).

• Garratt: type of articulated locomotive
• gauge: the width of gap between the rails on either side of the road.
• guard (UK): conductor (US)

• head-end power or HEP: A scheme whereby the locomotive engine (rather than a separate generator) provides power to carriages.
• hotel power (slang, US): That power used to provide for the comfort of passengers aboard a train en-route. See "HEP" above.

• injector: device to force water into a steam locomotive's boiler by steam pressure.
• island platform: a type of platform/track arrangement whereby a platform or platforms are entirely isolated from the main station by track running on either side of the platform area.

• loop (rail) (UK), siding (US): used on single-track railway lines, a loop is a second parallel set of tracks (running for a short distance), allowing two trains to pass by one another.

• Mallet: type of articulated locomotive designed by Anatole Mallet ("Mallee"). See "Compound Engine" above.
• Mogul: locomotive with a 2-6-0 wheel arrangement
• Multiple unit (UK): A self-propelled rail vehicle which can be joined with multiple compatible others and controlled from a single driving station. The sub-classes of this type of vehicle; Diesel Multiple Unit (DMU), Diesel-Electric Multiple Unit (DEMU) and Electric Multiple Unit (EMU) are more common terms. These may also be termed railcars.
• Multiple unit (US), Multiple working (UK): Generally seen as the abbreviation MU, this normally refers to the ability of most North American diesel and electric locomotives to be joined together and controlled from one driving station. Such a set of joined locomotives are called a consist or (colloquially) "lash-up" and are said to be "MUed together".
• Multiple working (UK): see Multiple unit (above).

• Pacific: locomotive with a 4-6-2 wheel arrangement
• points (UK): switch (US)
• pony truck:
• Prairie: locomotive with a 2-6-2 or 2-6-2T wheel arrangement
• push-pull: a mode of operation whereby a train may be driven in either direction without necessitating the locomotive to be at the forward end of the train.

• railcar: another term for Diesel Multiple Unit - DMU
• railroad (US): railway (UK)
• railway station (UK): train station (US)

• saddle: A plate which is bolted to sleepers, holding the rails in place.
• saddle tank: type of tank locomotive water tank.
• shunter (UK): switcher (USA) or shifter (PRR only): A small locomotive used for assembling trains and moving railroad cars around. Also, a person involved in such work.
• side tank: type of water tank.
• siding: a section of track off the main line used for storing rolling stock or freight. In the US the term is also used to cover the British term: loop.
• six foot: the narrow corridor between a pair of closely-spaced tracks, measing six feet, and the most dangerous place to stand. The boundary between a six foot, where one may be hit by a train, and the wider designation/width of ten foot, where one is usually safe, is hard to judge. See also four foot and ten foot.
• sleeper (UK), tie (US): Bars placed at 90 degrees to the rail tracks to support the rails. Generally of wood, concrete or steel, with various contraptions to affix the rails to the sleeper. Usually spikes, nails or bolts are used.
• spike: A bolt, pin or nail used to hold rails, or plates connected to the rails (known as saddles), to sleepers.
• smokestack (USA): chimney (UK)
• superelevation (UK): Synonymous with cant: the banking of railroad track on curves.
• superheater: A device for further heating the steam on a steam locomotive to increase power.
• switch (US): points (UK)
• switcher (USA), shunter (UK): A small locomotive used for assembling trains and moving railroad cars around.

• ten foot: an area, usually at least ten feet wide, between a pair of widely-spaced tracks, wide enough to form a place of safety in which railwaymen can stand while a train goes past. See also four foot and six foot.
• ten-wheeler (US): locomotive with a 4-6-0 wheel arrangement
• tie (US): sleeper (UK)
• through platform: the standard platform and track arrangement at a station. The train pulls alongside the platform, arriving from one end of the station, and may pass out the other side of the station by continuing along the same track.
• token: a physical object given to a locomotive driver to authorize him to use a particular stretch of single track.
• truck (US): bogie (UK)

• union station or union terminal: a train station in which tracks and facilities are shared by two or more railway companies.

• (goods) van (UK), boxcar (US): an enclosed railroad car, or piece of rolling stock, used to transport freight.

• well tank: type of tank locomotive water tank
• Whyte System: system of describing steam locomotive wheel arrangements, ie. "4-6-4", 2-10-2, etc. The first number indicates the "pilot" wheels that help lead the engine into turns. The second in the number of powered wheels ("drivers"). Third are the trailing idler wheels, usually to provide support to larger fireboxes.
• Wheel tapper: historical railway occupation; people employed to tap train wheels with hammers, with a view to listening to the sound made so as to determine the integrity of the wheel; cracked wheels, like cracked bells, do not sound the same as their intact counterparts. The job was associated with the steam age, and is an early form of acoustic investigation. Contemporary planned maintenance procedures have obviated need for the wheel-tapper.
• Wye: (UK: triangle): Three railroad tracks in a triangular form with switches at all three corners. With sufficient lengths of track leading away in all three directions, a wye can turn a train of any length.