I'm a train nerd. And I use lots of nerdy technical terms relating to trains as well as their histories and intricacies. So when I stop making sense and start talking about some obscure term... this is where to go!
Please keep in mind that all these terms are used in my North American (especially Canadian) part of the world. For those of you on other continents, you might have different names for some of these terms. And to be even more specific, not all of the terms on this list are used on all North American railroads. Some are interchangeable, and some aren't, such as "Clear to Stop" (Canadian railways use Clear to Stop) and "Approach" (American railways use Approach). Oh, also, I do not guarantee the accuracy of these terms but I strive to deliver it!
A-Unit = Locomotive with a cab and controls.
ABS = See "AUTOMATIC BLOCK SIGNALLING"
Absolute Signal = A signal which is controlled by a human operator. Trains are not allowed to pass an absolute signal displaying Rule 439 - Stop. Used in conjunction with CTC signals or in OCS territory, or on its own.
Automatic Block Signalling = A system where signals are controlled by track circuits and divides tracks into blocks. Signals controlled in this way can never be absolute signals.
B-Unit = Locomotive without a cab and sometimes controls.
Baggage Car = Railcar used to transport luggage and bags belonging to passengers on a consist.
Ballast = Small rocks or gravel underneath railway tracks that distribute the weight of the track and train evenly into the roadbed and ground.
Bell = Mechanical device or speaker mounted on a locomotive, control cab, or cabcar which emits a repeating sound.
Bogie = See "TRUCK"
Block = Section between two fixed signals. The signal at the beginning of the block "governs" it. A block can have two states - either unoccupied and therefore "clear" or occupied by a train.
Branch Line = A secondary and lesser-used railway track that branches off a main line. Usually considered as a subdivision.
Broad Gauge = A track gauge wider than standard gauge
Cab Unit = Locomotive with a body that extends the full length and width of a the locomotive. There is no visibility behind the train from the cab.
Canadian National = See "CANADIAN NATIONAL RAILWAY"
Canadian National Railway = A railway which was formerly a Canadian Crown Corporation founded in 1919 from the amalgamation of the Canadian Northern Railway and the Grand Trunk Pacific Railway. It is now a private company and spans Canada and the United States of America.
Canadian Northern Railway = A railway founded in 1899 which spanned Canada and one state in the United States of America. Was amalgamated with the Grand Trunk Pacific Railway in 1919 to form the Canadian National Railway.
Canadian Pacific = See "CPKC"
Canadian Pacific Railway = See "CPKC"
Cab = Room inside a locomotive, control cab, or cabcar used to control the locomotive(s).
Cabcar = A railcar other than a locomotive, slug, snail, or control cab with a cab and cab controls that can control a locomotive (or multiple locomotives) somewhere in the consist that it is part of.
Caboose = Railcar no longer in widespread use on railroads. Typically coupled behind the locomotives at the head end of the train or at the tail end. Used to provide accommodation to the tail-end crew of a train. Often equipped with a cupola to view the train with. Caboose was phased out due to the End Of Train Device coming into use.
Car = See "ROLLING STOCK"
Car Float = A boat (usually a barge pulled by a tugboat) that transports railcars from one side of a body of water to the other.
Carload Frieght = Frieght service involving small loads of goods in one railcar moving between certain customers.
Centralized Traffic Control = A system that allows a single person to control signals and switches from a certain location. This signalling system is used most often on higher-traffic lines.
Chop Nose = A hood unit that originally had a high short hood but was retrofitted with a low short hood.
Consist = Two or more railcars coupled together. (pronounced COHN-sist)
Continuous Welded Rail = Long sections of rail that have been welded together to form one long rail.
Control Cab = A slug or snail with a cab and controls. This does not mean that it is controllable on its own as it still needs a "mother" unit (an actual locomotive). The controls in the cab of the control cab control the "mother" unit, as slugs and snails are uncontrollable and can only be controlled by a locomotive.
Cowl Unit = Similar to a cab unit, except the body is merely a frame and does not provide structural support.
Coupler = See "COUPLING"
Coupling = Device used to connect one railcar to another.
CN = See "CANADIAN NATIONAL RAILWAY"
CNoR = See "CANADIAN NORTHERN RAILWAY"
CNR = See "CANADIAN NATIONAL RAILWAY"
CP = See "CPKC"
CPKC = A railway founded in 1881 which now spans North America. It was known as CP Rail between 1968 to 1996, and after a major merger with the Kansas City Southern Railroad in 2023, it is now known as CPKC (editorial: I really don't like the name CPKC. It doesn't roll off the tongue the way Canadian Pacific or CP Rail did.).
CPR = See "CPKC"
CP Rail = See "CPKC"
CROR = Canadian Rail Operating Rules
CTC = See "CENTRALIZED TRAFFIC CONTROL"
Crosstie = See "TIE"
CWR = See "CONTINOUS WELDED RAIL"
CN = See "CANADIAN NATIONAL RAILWAY"
CNoR = See "CANADIAN NORTHERN RAILWAY"
CNR = See "CANADIAN NATIONAL RAILWAY"
Dark Territory = Track without signals
Diamond = A junction of two railway tracks crossing each other at grade (at the same height)
Ditch Lights = Lights underneath and on either side of the headlight used to illuminate the areas beside the roadbed.
Diverging = This website's name and Rule 430 of the Canadian Rail Operating Rules.
Draper Taper = Name of a refinement made to the cowl unit, where the frame of the locomotive tapers in slightly to allow visibility out the back of the cap.
Drumhead = Railroad's logo mounted on the rear of the train, usually on an observation car.
Drumplate = See "DRUMHEAD"
EOTD = See "END OF TRAIN DEVICE"
EMD = General Motors Electro-Motive Division
End Of Train Device = Device attached to the rear of a train which monitors brake pressure and other important stats. Replaced the caboose, for the most part.
Fixed Signal = A signal that permanently remains in one location and is usually electrically or mechanically controlled remotely.
Flashing Rear End Device = See "END OF TRAIN DEVICE"
FRED= See "END OF TRAIN DEVICE"
Freight Car = A railcar used to transport freight.
Gauge = The distance between two rails on a railway track.
GE = General Electric
Grade Crossing = A place where a roadway crosses a railway track at the same height.
Grade Crossing Signal = A warning signal, often controlled by track circuits, which warn motorists of oncoming trains. Grade crossing signals can consist of flashing lights, bells or speakers, and boom gates.
Grand Trunk Pacific = See "GRAND TRUNK PACIFIC RAILWAY"
Grand Trunk Pacific Railway = A railway founded in 1914 and spanned Canada. Was amalgamated with the Canadian Northern Railway in 1919 to create the Canadian National Railway.
GTP = See "GRAND TRUNK PACIFIC RAILWAY"
Handcar = A small, human-powered railcar used for the transport of section crews. Was replaced by the speeder.
Head End = The front of a train
Head End Power = See "HEP"
Headlight = A bright light mounted on the front and rear of a locomotive, control cab, slug, and snail, on the rear of an observation car, and the front of a cabcar. Used to illuminate the track in front of the train.
HEP = The electrical system on a passenger train used to power necessities like heating, lighting, etc
HEP Generator = A generator used to generate the power used by the HEP system.
High Hood = When the hood of a hood unit is as high as the cab. It is most common to see a high long hood and a low short hood on hood units.
Hood Unit = Locomotive with a cab as wide as the underframe of the locomotive, but the rest of the locomotive (hood) is narrower, allowing for walkways on the side of the locomotive.
Horn = See "WHISTLE"
Hi-Rail = See "HY-RAIL"
Hy-Rail = A vehicle capable of travelling on both roads and railway tracks.
Juxtaposition = The fact of two things being seen or placed close together with contrasting effect.
Jointed Rail = Shorter sections of rail which are connected with rail joiners.
Lead = Spur track serving multiple industries (Pronounced "LEED")
Locomotive = Railcar which uses a fuel such as steam, diesel, electricity, or hydrogen to move other railcars. Usually but not necessarily equipped with a cab to control the unit.
Long Hood = The longer of two hoods on a hood unit. Although not always, long hoods are most commonly the rear of the locomotive.
Low Hood = On hood units, a low hood is when the hood is roughly half the height of the cab. It is rare to see hood units with low long hoods with the exception of slugs.
Maintenance Of Way = The act of maintaining a railroad line and the surrounding area. Equipment used for this purpose is often known as Maintenance Of Way (usually shortened to MOW) equipment.
Motorcar = See "SPEEDER"
MOW = See "MAINTENANCE OF WAY"
MOfW = See "MAINTENANCE OF WAY"
Narrow Gauge = A track gauge narrower than standard gauge.
Numberboard = Illuminated board on the front and sometimes rear of a locomotive which displays the road number.
Observation Car = A passenger car which usually sits at the tail end of the train and allows passengers to have a very clear view outside of the train. Some older observation cars have balconies at the rear.
Occupancy Control System = A system where train crews receive clearance from a dispatcher to enter and move a train within a certain subdivision or spur.
OCS = See "OCCUPANCY CONTROL SYSTEM"
Passenger Car = A railcar used to transport people.
Prime Mover = Device on a locomotive that converts fuel into work. This would be the diesel engine on any type of diesel locomotive, or the hydrogen fuel cells on a hydrogen locomotive.
Pumpcar = See "HANDCAR"
Rail = A steel bar laid in a continuous line of others to form a railway track. Another line of rails runs parallel to the first.
Railbed = See "ROADBED"
Railcar = An "umbrella term" for all vehicles that travel on a railway track, with the exception of Hy-Rail equipment.
Railfan = Someone (like me) with an ̶u̶n̶h̶e̶a̶l̶t̶h̶y̶ ̶o̶b̶s̶e̶s̶s̶i̶o̶n̶ interest in trains.
Rail Joiner = Small metal plate which houses the bolts used to connect segments of jointed rail together.
Reporting Mark = A string of 2-4 letters stencilled on the side of most railcars identifying its owner.
Ribbon Rail = See "CONTINOUS WELDED RAIL"
Roadbed = The foundation in which railway tracks are laid. Roadbeds usually consist of earth and ballast. Often, roadbeds will remain even after tracks have been removed.
Road Crossing = See "GRADE CROSSING"
Road Number = Identification number of a railcar, usually printed on numberboards or stencilled on the side, front, and/or rear of the railcar.
Rolling Stock = All non-locomotive railcars.
Short Hood = The shorter of two hoods on a hood unit. Some short hoods are as wide as the cab and although not always, short hoods are most commonly the front of the locomotive.
Signal = A sign, light, flag, hand movement, whistle pattern or other device, sometimes used together to convey information to a train crew.
Semaphore Signal = An early type of fixed signal used on railways that uses a moving arm to convey signal indications.
Signal Aspect = The visual appearance of a railroad signal, for instance: a red light over a green light or a horizontal semaphore arm over a vertical semaphore arm.
Signal Indication = The meaning of a signal aspect. In the above example, that signal would be Rule 431 of the Canadian Rail Operating Rules: Slow to Clear.
Siding = A short track that comes off of the main track of a railroad line (could be a main, branch, or spur line), runs relatively parallel to it and connects back to it farther down the track. Used to store railcars or let trains pass each other.
Sleeper = See "TIE"
Slug = A cabless (and uncontrollable unless coupled to a locomotive) rebuilt locomotive with its prime mover removed but retains its traction motors. The traction motors draw excess current from a "mother" locomotive. Therefore, slugs can only work when coupled and connected to locomotives. Slugs are not locomotives as locomotives have traction motors and prime movers.
Snail = A cabless (and uncontrollable unless coupled to a locomotive) rebuilt locomotive with its traction motors removed but retains its prime mover. The prime mover is used to power other engineless units. Therefore, snails can only work when coupled to a "mother" locomotive. Snails are not locomotives, as locomotives have traction motors and prime movers.
Speeder = A small gasoline-powered railcar used to move work crews to and from areas on a railway track. Replaced the handcar, and known as a speeder since it is faster than a handcar or plain old walking although it is quite slow compared to an actual train. The speeder is also known very commonly as a motorcar.
Spur = A track almost always shorter than a branch line that branches off a main line, branch line or other spur line. Spur tracks usually have only one connection point to its "parent" line, often making them dead ends. Often used to serve industries or store railcars. Sometimes spur tracks are former subdivisions that have been cut short.
Standard Gauge = The standard track gauge across the world and is used on 55% of all railway lines. The distance between rails on standard gauge is 4 feet and 8.5 inches, or 143.5 centimetres.
Subdivision = A section of railroad track governed by a certain timetable and set of rules. Most branch lines are single subdivisions, and most main lines are broken into various subdivisions. Most subdivisions connect one subdivision to another, however this is not always the case.
Switch = Type of track that can be moved back and forth to direct trains onto another track.
Tail End = The rear end of a train.
Tie = A wooden, concrete, or sometimes plastic/rubber beam that rails are connected with.
Throttle = Device used on locomotives, cabcars, and control cabs to regulate the speed of the train.
Track = Two parallel pieces of steel connected with ties in which trains run on.
Trackbed = See "ROADBED"
Track Circuit = An electrical circuit flowing through the rails on both sides of the track. When a train passes over the rails, it shorts out the circuit and this can be used to detect the presence or absence of a train. This can be adapted into a signalling system such as CTC or ABS or to control grade crossing signals.
Traction Motor = An electric motor connected to the axle of a locomotive mounted to the truck. Turns the axle to move the locomotive. Used on diesel-electric, electric, and hydrogen locomotives.
Train = One or more railcars.
Train Crossing = See "GRADE CROSSING"
Trainz = See "TRAIN SIMULATOR"
Trainz 2019 = See "TRAIN SIMULATOR"
Trainz Railroad Simulator 2019 = See "TRAIN SIMULATOR"
Train Simulator = A computer based simulation of rail transport operations.
Truck = Assembly housing wheels and axles on a railcar.
TTC = Toronto Transit Commission
Whistle = Steam or air-operated device used to make a loud, continuous sound.
Wye = A triangle of railroad tracks with a switch connecting two tracks at each vertex of the triangle. A wye is used for turning trains 180°, are space efficient, and allow whole consists to be turned (which is something turntables cannot do). (See the Wikipedia article on wyes for more info)