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Railroad Glossary: Terms, Slang, Definitions & Meanings

Last revised: September 4, 2026

By: Adam Burns

American railroads have been running long enough to grow a language of their own. Some of it is engineering (tractive effort, ruling grade). Some of it is traffic and law (waybill, Staggers, Class I). A lot of it is slang that outlived the hardware: a highball was once a ball hoisted on a mast; crews still say it for a clear, full-speed railroad. Flimsies were the tissue paper train orders were written on. A FRED on the last car replaced the caboose most of the public still looks for.

This page is the sitewide glossary for that general language—operations, traffic, corporate terms, and crew talk. It is not a complete dictionary of every shop word, and it does not repeat the specialized lists already on American-Rails.com. Steam locomotive parts and type names live on steam terms. Track, structures, and property words have their own leaves and the property glossary. Careers and hiring are on railroad jobs. Dedicated articles (tell-tales, ditch lights, gandy dancers, the crossbuck) are listed at the bottom; only pages that already exist are linked.

Union Pacific 4-6-6-4 #3803 climbs Archer Hill, just east of Cheyenne, Wyoming, August 31, 1955. J.E. Shaw photo. American-Rails.com collection.

On this page: At a glance · A–B · C · D–E · F–G · H–I · J–L · M–O · P–R · S · T–Z · Term articles · Related reading

At a glance

Definitions below are working English for readers and railfans, not operating-rule substitutes. Restricted speed, hours of service, and trackage-rights contracts are set by railroad timetables, GCOR/NORAC, the FRA, and the STB. When a term has a full article, that page is the place for the history.

A–B

ABS (Automatic Block Signal): A wayside signal system that detects track occupancy and displays indications without a dispatcher lining each move. Not the same as CTC, where the dispatcher also controls switches and signals from a machine.

Adhesion factor: The share of a locomotive’s weight on driving wheels that can be used for tractive effort, expressed as a percentage. Multiply that percentage by weight on drivers to estimate tractive effort. Wet rail, sand, and wheel slip all change the real number.

AEI (Automatic Equipment Identification): Wayside scanners that read RFID tags on cars and locomotives so railroads can track consists. Standard on Class I lines.

Affiliate: A company owned or controlled by another.

AAR: Association of American Railroads, the freight-rail trade association. It is not the regulator (that is the FRA for safety and the STB for economics).

Availability: The share of time a locomotive is ready for assignment rather than shopped, wrecked, or otherwise out of service. The old copy on this page said a unit was available and down; those are opposites.

Bad order: A car or locomotive barred from service for a defect. Car inspectors card the equipment; it stays bad-ordered until repaired or shopped.

Ballast: Crushed stone (sometimes slag or other rock) that holds ties in place, spreads load, and drains the track. See rail maintenance.

Belt line: A railroad that works in and around a city, often connecting other roads’ terminals rather than running a long-haul main line of its own.

BLE / BLET: Brotherhood of Locomotive Engineers, founded in the 1860s. In 2004 it became the Brotherhood of Locomotive Engineers and Trainmen (BLET) under the Teamsters. See BLET.

Blue flag: A blue flag, light, or tag on equipment that means people are working on it. Blue-flagged cars and engines must not be coupled to or moved. A motive-power glossary term that belongs in every yard.

Boomer: A railroader who drifted from job to job and road to road, especially in the steam era.

Brakeman: Historically the person who tied hand brakes and protected shoves; on today’s Class I freight the surviving train-service jobs are usually engineer and conductor. History: brakeman.

Bridge route: A railroad that handles more overhead (through) traffic than freight it originates or terminates itself.

Bridge traffic (overhead traffic): Freight received from one railroad, hauled by a second, and delivered to a third.

Bulk: Commodities moved in volume without packages: coal, grain, ore, soda ash, plastic pellets, petroleum, liquid sweeteners, and the like.

Bulletin order: A written notice to employees of a temporary operating change—slow orders, track out of service, a detour, a special move.

Ferrocarriles Nacionales de México (NdeM) B23-7 #10018 at Railfair ’81 in Sacramento, May 1981. Fred Nicas photo. American-Rails.com collection.

C

Caboose: The conductor’s car on the rear of a freight, office and lodging for the crew, with markers that said the train was complete. End-of-train devices replaced most cabooses in the 1980s. See caboose and EOT / FRED.

Charter: The state (or federal) act that creates a corporation and grants its rights. Early American railroads were creatures of legislative charters.

Class I, II, III: Federal size classes by annual operating revenue, set today by the Surface Transportation Board. In 2025 the Class I floor is about $1.095 billion; Class II about $49.1 million; Class III below that. The AAR counts six North American Class I freights in U.S. service (BNSF, UP, CSX, NS, CN, CPKC). Details: Class I · regionals · short lines.

Clearance diagram (loading gauge): The height and width envelope a line can accept—tunnels, bridges, platforms, double-stack well cars. Not the same as the weight limit.

Clearance form: In timetable-and-train-order territory, the paper an operator issued showing a train which orders it held, in sequence.

COFC: Containers on flatcar (or in well cars). Sister term: TOFC, trailers on flatcar.

Cog railroad: A railroad that climbs grades too steep for adhesion alone, using a toothed wheel in a rack rail. The Mount Washington Cog Railway is the classic American example.

Common carrier: A company that holds itself out to the public to haul goods (or passengers) for hire. The Baltimore & Ohio is the usual first U.S. common-carrier railroad (chartered 1827). See common carrier.

Commuter service: Short-haul passenger trains timed for the workday, usually city-to-suburb. Not intercity Amtrak, and not the old interurban. See commuter rail.

Company-owned railroad: A railroad whose stock is held by another company rather than traded as an independent.

Conductor: The person in charge of the train—crew, paperwork, and (with the engineer) safe movement. See conductor.

Consignee: The party who receives a freight shipment.

Consist: The makeup of a train: locomotives, cars, and their order. Also used for a locomotive set working together.

Consolidation: In corporate language, merging two companies into a new one. In steam, a 2-8-0. The wheel arrangement has its own page; this glossary means the legal sense unless a caption says otherwise.

Container: A box built to be lifted between ship, rail, and truck. ISO boxes are commonly 20 and 40 feet; North American domestic containers are often 53 feet. The old copy on this page said “standardized 40-foot” as if that were the only size.

Controlling interest: Enough stock to control a corporation, not always 50 percent plus one in practice, but that is the usual test for a subsidiary.

Coupler (knuckle): The Janney-type knuckle coupler used in North America. The knuckle is the moving piece that locks into the facing coupler. See couplers.

CP (control point): A named location in CTC or similar territory where the dispatcher can control signals and/or switches. Not Canadian Pacific, unless the caption is about that railroad.

Crossbuck: The X-shaped grade-crossing sign. Passive is the sign alone; active adds lights and often gates. See crossbuck.

CTC (Centralized Traffic Control): A signal system in which a dispatcher, from a machine, lines switches and signals over a territory. Occupancy is still detected automatically; the dispatcher decides who gets the railroad.

Cut: A group of cars coupled together. Also an excavation through a hill for the track, as opposed to a fill or a tunnel.

D–E

Dark territory: Track without wayside block signals. Authority comes from track warrant, Form D, or older train-order methods, not from green lights in the field.

Deadhead: To move a person or a piece of equipment on a train without it doing work—a crew repositioning, an empty cab car, a locomotive towed shut down.

Defect detector: A wayside box that listens for hot journals, dragging equipment, or shifted loads and radios the train. Replaced a lot of caboose flagging and roll-by inspection.

Degree of curve: How sharp a curve is. In U.S. railroad practice, the central angle subtended by a 100-foot chord.

Departure yard: Yard tracks where an outbound train is assembled and made ready to leave.

Derail: To leave the rails. Also a track device, usually on a spur or siding, that will dump a runaway car rather than let it foul the main.

Derating: Turning down a diesel’s horsepower—by software or mechanical change—to save fuel or spare the engine.

Dispatcher: The person who grants track authority and runs the railroad over a district. See dispatcher.

Ditch lights: Auxiliary headlights low on the nose, required by FRA rule (1996) on locomotives that take public crossings above 20 mph. They form a triangle with the main headlight. See ditch lights.

Double the hill: To take a train up a grade in two pieces because the power cannot lift it as one.

Doubleheading: Two locomotives on the point, each with its own crew in steam days; today usually MU’d as one consist. See doubleheading.

Double-stack: Two containers, one in the well and one on top, on a well car. Needs plate-H (or equivalent) clearances.

Distributed power (DPU): Radio-controlled locomotives cut into a train or on the rear, so the engineer on the point works more than one set of units. Helpers without a second crew on the rear engine.

Drag: Slang for a slow, heavy freight.

Drawbar force (drawbar pull): Force available at the coupler to move the train—tractive effort minus what it takes to move the locomotive itself. The old copy on this page had the subtraction backwards.

Drayage: The truck move at either end of an intermodal shipment, terminal to customer or the reverse.

Dual-mode: A locomotive that can run as a diesel-electric and also take electric power—third rail (Amtrak P32AC-DM, Metro-North) or, on some designs, overhead catenary. The old definition here mentioned only third rail.

Dual-service: A locomotive assigned to both freight and passenger work, or designed for both.

Dump the air: To make an emergency brake application, putting the train line to atmosphere.

Dynamic braking: Using the traction motors as generators so the train slows on the downhill without riding the air. Standard on road diesels.

Eighth notch (Run 8): The last, maximum position on a diesel throttle. Eight notches is the usual North American controller.

Embargo: A railroad (or a regulator) temporarily closing a line or a commodity move—washout, congestion, a plant that cannot take cars.

Engineer: The person at the throttle. Slang: hogger, hoghead. A hostler is not another word for engineer; a hostler moves locomotives around the engine terminal. See engineer.

EOT / ETD / FRED: End-of-train device; Flashing Rear End Device in older talk. A box on the last coupler that monitors brake-pipe pressure, flashes red, and (on two-way units) can dump the air from the rear. See end-of-train device.

Extra (extra train): A train not scheduled in the timetable, identified by engine number and direction. In train-order days extras were inferior to regular trains unless given rights.

Extra board: The pool of train-service employees not assigned to a regular job, called as needed.

Rio Grande GP9 #5922 switching customers in Aspen, Colorado, at the end of the Aspen Branch, 1970s. American-Rails.com collection.

F–G

Fallen flag: A railroad that no longer exists under that name—merged, abandoned, or renamed. See fallen flags.

First trick: The day shift, traditionally 8 a.m. to 4 p.m. Second trick is afternoon; third (or “hoot owl”) is nights. Usage varies by road.

Flimsies: Train orders written on thin tissue so a tower operator could make carbons. The word stuck for the orders themselves.

Form D: Written movement authority used on NORAC railroads in the East. GCOR territory uses a track warrant for the same job.

FRA: Federal Railroad Administration, the U.S. safety regulator.

Frog: The crossing piece in a turnout or a diamond where wheel flanges must pass through a gap. See diamonds and property terms.

Full-service trackage rights: A tenant railroad may serve customers on the owner’s line, not merely run through. Contrast overhead (bridge) trackage rights.

Fusee: A railroad flare, used for flagging and emergency protection.

Gandy dancer: Slang for a section hand who lined, spiked, and tamped track by hand. The “Gandy Manufacturing Company of Chicago” story is folklore, not a proven etymology. See gandy dancers.

Gauge: Distance between the inner faces of the rails. North American standard gauge is 4 feet 8½ inches. Narrower is narrow gauge.

Golden State Route: The Chicago–Los Angeles corridor historically associated with the Rock Island and Southern Pacific Golden State, with connecting pieces later under Union Pacific. Treat it as a named passenger/freight route, not a glossary of all UP lines to El Paso.

Granger roads: Midwestern and Plains railroads that lived on grain and farm traffic: Chicago & North Western, Chicago Great Western, Minneapolis & St. Louis, Rock Island, Milwaukee Road, Burlington, and their neighbors. See Granger railroads.

Gross ton-mile: Weight of cars plus lading, moved one mile. Net ton-mile counts only the freight.

H–I

Haulage: Railroad A pays Railroad B to move A’s cars with B’s crews and power. A does not run its own trains on B’s tracks. Different from trackage rights, where A runs its own trains.

Helper (pusher): Extra locomotives cut in to lift a train over a grade, then cut off. Distributed power is the radio-controlled cousin.

Highball: Proceed at normal speed; the railroad is yours. From ball signals: the ball hoisted high meant clear. See highball.

Hi-rail (hy-rail): A highway truck with retractable flanged wheels so it can run on the rails. Hy-Rail is a Fairmont trademark; hi-rail is the usual spelling.

Hogger: Slang for locomotive engineer. Hog law is hours of service.

Holding company: A company that controls others through stock ownership.

Hostler: An engine-terminal employee who moves locomotives between shop, fuel, sand, and the ready track. Not a road engineer.

Hotbox (hot journal): An overheating axle bearing. Defect detectors and roller bearings made the classic hotbox rarer; it is still a derailment risk. See hotbox.

Hotshot: A high-priority freight that keeps the main and does not wait for drags.

Hours of service (hog law): Federal limits on how long train employees may remain on duty. The number crews still quote is 12 consecutive hours, then required rest. The statute and FRA rules have been amended; this glossary is not the current 49 U.S.C. § 21103 text.

Hump: A small hill in a classification yard. Cars are shoved over the crest and roll into class tracks under retarders. Flat switching does the same work without the hill.

In the hole: In a siding, usually waiting for a meet or a pass.

Incentive per diem: An ICC-era (1970s) extra daily charge on certain boxcars, meant to ease a car shortage and to encourage new cars. Short lines bought fleets; surplus and deregulation ended the boom.

Industrial railroad: A plant railroad that switches the owner’s property and does not hold itself out as a common carrier (or does so only in a limited way).

Interchange: The junction, and the act, of handing cars from one railroad to another.

Intermodal: Freight that moves by more than one mode in the same box or on the same trailer—rail plus truck, plus ship for overseas boxes. On the railroad it usually means TOFC, COFC, and double-stack.

Interurban: An electric railway that connected cities and towns, often with street running in town, booming about 1890–1930. It is not modern light rail and not commuter rail, even when a new streetcar occupies an old interurban grade. See interurbans.

Union Pacific 2-8-0 #533 at Rawlins, Wyoming, September 4, 1956. C-57 class Consolidation, built in UP shops in 1918 for the Oregon Short Line. J.E. Shaw photo. American-Rails.com collection.

J–L

Joint operation: Two railroads operating as one on the ground while keeping separate boards and books. Joint track is the physical version: two companies, one pair of rails, agreed rules.

Knuckle: See coupler.

Lading: The freight in the car.

LCL: Less-than-carload. Small shipments that once filled house cars and wayfreights; trucks took most of it after World War II.

Lignite: Low-rank coal. Northern Pacific sized its first 4-8-4s around Rosebud lignite and a huge grate; see the 4-8-4 page.

Line-haul railroad: A carrier that takes freight from one point to another, as opposed to a switching-and-terminal road that only works a terminal district. Today it covers Class Is, regionals, and many short lines.

Load limit: Maximum weight a car, bridge, or line may carry. Related: 286,000-pound (286k) cars on lines upgraded for them.

Loading gauge: See clearance diagram.

Local (wayfreight): A freight that works the industries and sidings on a district rather than running through. Burlington people said wayfreight; other roads said local, peddler, or turns.

M–O

Main line (main track): The running track between terminals, as opposed to yard tracks, sidings, and spurs. Two mains are double track.

Manifest: The list of what each car is carrying. Also a mixed freight that is not a unit train or a pure intermodal stack train.

Marker: The rear-end signal that the train is complete. Oil lanterns and electric markers on cabooses; today the flashing EOT. See EOT.

Mars light: An oscillating auxiliary headlight (Mars Signal Light Company), often a figure-8 beam, used for grade-crossing warning. Ditch lights and FRA rules retired most of them from the main line. See Mars light.

Meet: Two trains passing on single track, one in the hole.

Merger: One corporation absorbing another. Different legal mechanics from a consolidation into a new company; crews use both words for the same headache.

Mixed train: Freight and passengers in the same train, common on branch lines into the mid-twentieth century.

MU (multiple unit): Jumpers and hoses that let one engineer control several diesel or electric locomotives as one.

Name train: A passenger train with a name, not only a number—Broadway Limited, Super Chief. A few freights were named the same way and rated as hotshots.

Narrow gauge: Track narrower than 4 feet 8½ inches. In the U.S. the common historic gauge was 3 feet. See narrow gauge.

Net ton-mile: One ton of freight moved one mile, the basic traffic statistic.

Nominal (rating): The nameplate horsepower or tractive effort of a locomotive, whether or not it is making that number today.

On the ground: Derailed.

Operating ratio: Operating expenses divided by operating revenue. Lower is better. An old rule of thumb treated anything over 80 percent as unhealthy; modern Class I targets are often in the 60s. It is a management metric, not a law of physics.

OS: On sheet. The operator’s report that a train has passed the station, from timetable-and-train-order days. See stations.

Overhead trackage rights: The tenant may run trains over the owner’s rails but may not serve local customers. Also called bridge rights.

Overhead traffic: See bridge traffic.

Missouri-Kansas-Texas (Katy) GP40 #172 at the terminal in Parsons, Kansas, circa 1969. American-Rails.com collection.

P–R

Per diem: The daily charge a car owner bills another railroad for using the car. Latin for “per day.”

Pickup: Adding cars to a train en route.

Pole line: The open-wire telegraph, telephone, and signal circuits that once followed almost every main line. See pole lines.

Pooling agreement: Competing railroads sharing earnings on a route so that it did not matter which company hauled the cars. Common in the nineteenth century; later antitrust law took a dim view.

Powder River Basin (PRB): The coal field of northeastern Wyoming and southeastern Montana, the dominant U.S. rail coal origin since the 1970s–80s.

Power: Locomotives.

Profile: A drawing of a line’s grades and elevations, the picture that shows the ruling grade.

PTC (Positive Train Control): A processor-based overlay that can stop a train for a missed signal, overspeed, or misaligned switch. Federally mandated on many U.S. passenger and certain freight lines after the 2008 Rail Safety Improvement Act; implementation stretched into the 2020s.

Receivership: A bankrupt railroad run by a court-appointed receiver.

Recrew (dog-catch): Sending a fresh crew to a train whose on-duty time has run out under hours of service.

Regional railroad: In ordinary talk, a Class II: larger than a short line, smaller than a Class I. See regionals.

Reporting marks: One to four letters identifying the owner or lessee of a car or locomotive, stenciled on the equipment. A mark ending in X is a private owner, not a railroad (TILX, GATX). Marks are registered through the AAR.

Restricted speed: A defined operating-rule speed: slow enough to stop within half the range of vision short of a train, a misaligned switch, a broken rail, or an obstruction, and not exceeding the rulebook maximum (GCOR commonly 20 mph; NORAC 15 mph). It is not a single nationwide number.

Right-of-way: The railroad’s strip: track, roadbed, ditches, and the land they sit on.

RIP track: Repair-in-place track, where carmen work bad-ordered cars in the yard instead of sending them to a backshop.

Roadmaster: The supervisor responsible for track on a territory. See roadmaster.

Road number: The number painted on a locomotive for operating identity, as opposed to a builder serial.

Roadbed: The graded earth (and drainage) that supports ballast, ties, and rail.

Roll-by: Inspecting a train as it passes—hot journals, shifted loads, dragging equipment, a smoke trail.

Rolling stock: Cars, and often locomotives, as a class of equipment. See rolling stock.

Route mile: The geographic length of a line, counting the route once. Track-miles count every main, siding, and extra track.

Ruling grade: The steepest pitch that sets how much tonnage a given locomotive can take over the district.

Run 8: See eighth notch.

Runaround: A locomotive leaving its train, using a parallel track, and coupling to the other end. Also the track that lets you do it.

Run-through: A train that does not work en route—no setouts, no pickups.

S

Section hand: Track laborer assigned to a section gang. See gandy dancer and track laborer.

Section house: Company housing for a section foreman or maintainers. See section house.

Semaphore: A signal whose indication is given by the position of a blade (and usually a light). See semaphores.

Set out: Leaving a car or a cut at a siding, spur, or yard.

Short line: In ordinary talk, a Class III freight railroad. See short lines.

Shorthaul: Moving a shipment a shorter distance than the long-haul route between two points, then handing it off. Also used for a railroad that only has a short piece of a long move.

Short-time rating: The higher amperage a traction motor can take for a few minutes without damage, above its continuous rating. Grades and starts use it; abuse cooks the motor.

Siding: An auxiliary track beside the main, used for meets and passes. A spur usually serves an industry and is not for meeting trains.

Single-line haul: Origin to destination on one railroad, no interchange.

SIT: Storage in transit. Holding a commodity (often grain) in cars under a tariff that treats the storage as part of the move.

Slack action: The gather and run-out of slack in couplers and draft gear. On a long train it can break knuckles or put cars on the ground if the engineer is careless.

Spot a car: Place it at the exact door, dump, or unloading point the customer needs.

Spur: A stub track, usually to an industry.

Stabbing: An unexpected delay to a train.

Stack train: An intermodal train of double-stack well cars.

Staggers Act: The Staggers Rail Act of 1980, signed October 14, 1980, which largely deregulated railroad rates and contracts. Named for Rep. Harley O. Staggers of West Virginia. See industry history.

STB: Surface Transportation Board, the federal economic regulator that succeeded the ICC in 1996.

Subsidiary: A company more than 50 percent owned by another.

Superelevation: Banking a curve by raising the outside rail so speed does not throw the train to the high side.

Switching district: An area where more than one railroad can serve the same shippers, by reciprocal switching or by having their own spurs.

T–Z

Tariff: The published rates and rules for a move. Contracts after Staggers took much of the romance out of the public tariff, but the word remains.

Tell-tale: A row of hanging ropes or chains before a low bridge or tunnel, meant to warn a brakeman on a car roof. Rooftop braking ended; tell-tales mostly came down. See tell-tales.

Terminal: Where trains are made up, broken up, and dispatched—yards, enginehouses, and the throat tracks. Also a large passenger station. See stations and yards.

Terminal railroad: A switching-and-terminal company that works a city or a harbor for line-haul roads, rather than running its own long-distance freights. Chicago remains the textbook.

Through freight: A train not scheduled to work en route. Same idea as run-through.

Tires: The steel rims shrunk onto steam (and some early) driving-wheel centers. A steam-shop term; see steam terms.

TOFC: Trailer on flatcar; piggyback.

Tonnage rating: How many tons a locomotive (or a consist) is allowed over a district, set by tractive effort and the ruling grade.

Ton-mile: See net ton-mile.

Track warrant (TWC): GCOR written or radio authority to occupy main track in dark or warrant territory. NORAC’s cousin is Form D.

Trackage rights: One railroad running its trains over another’s tracks, by contract. Overhead rights are through only; full-service rights include local work.

Tractive effort (tractive force): The force, in pounds, a locomotive can exert at the rail to start and pull a train. A common estimate is adhesion factor times weight on drivers. Not the same as horsepower, which is about sustaining speed.

Trailing truck: The unpowered wheels under the cab and firebox of a steam locomotive (the last number in Whyte notation: the 4 in 4-8-4). See steam terms and 4-8-4.

Train line: The continuous brake pipe through the train. When it is charged and intact, the engineer has the air.

Train order: Written authority, copied by an operator and handed up (or radioed in later years), that created extras, gave rights, and ran the railroad with the timetable. Form 19 and Form 31 were the usual blanks. See stations.

Transit: Urban public transportation—subway, light rail, streetcar, bus. Commuter rail is related but not the same word. Do not use transit for every passenger train.

Truck: The wheel-axle-frame assembly under a car or locomotive. Not a highway truck, unless the caption is about drayage.

Turntable: A rotating bridge that turns a locomotive in a roundhouse yard. See turntables.

UDE (undesired emergency): An emergency brake application the engineer did not call for—a parted train line, a kicked valve, a derailment.

Unit train: A train of one commodity, origin to destination, without intermediate switching: coal, grain, crude, potash.

Varnish: Passenger equipment. From the high-gloss varnish on wood cars. The word is still used for passenger trains and heritage cars. (The previous version of this page ended mid-sentence here.)

Waybill: The document that travels with a shipment: shipper, consignee, route, car initials and number, commodity, weight, and billing.

Wayfreight: See local.

Wheel slip: Drivers turning faster than the train is moving. Sand, a lighter throttle, and modern wheel-slip control are the answers; untreated slip burns rail and does not pull.

Whyte notation: The leading-drivers-trailing count for steam locomotives (4-8-4, 2-8-2, 4-8-8-4). See steam locomotives.

Wigwag: A grade-crossing signal with a swinging target and a light, once common in the West. See wigwag signals.

Work train: A non-revenue train for maintenance of way: ballast, rail, ties, ditching, wrecking.

Wye: Three tracks in a triangle, used to turn equipment or to branch in two directions. Not a turntable and not a balloon track.

Zombie: Shop slang for a low-power rebuild that keeps a donor locomotive’s frame and trucks and hangs a smaller engine on them.

Rio Grande SD45 #5339 and GP40 #3075 in Pueblo, Colorado, circa 1969. American-Rails.com collection.

Term articles on American-Rails.com

These are the dedicated leaves already on the site. Definitions above stay short; the article is the place for the full story. More leaves can be added without rewriting this hub except to drop in a link.

Operations, signals, and slang

• Highball
• Doubleheading
• Semaphores
• Wigwag signals
• Crossbuck
• Tell-tales
• Hotbox
• End-of-train device (FRED)
• Ditch lights
• Mars light

Track, structures, and property

• Property terms
• Infrastructure
• Diamonds (crossing frogs)
• Pole lines
• Section house
• Turntables
• Water tanks
• Water standpipe
• Gandy dancers
• Stations and depots
• Yards

Cars, brakes, and motive power

• Rolling stock terms
• Motive power terms
• Steam locomotive terms
• Caboose
• Couplers
• Automatic air brake (Westinghouse)
• Cowcatcher / pilot
• Common carrier

Labor, companies, and culture

• BLET
• Railroad organizations
• Railroad jobs
• Granger railroads
• Warbonnet livery
• Railfans

Related reading

• U.S. railroad history · Fallen flags
• Steam locomotives · Diesels · Locomotive history
• Class I railroads · Maintenance
• Freight cars · Passenger cars

Sources for this rewrite include the previous American-Rails glossary (August 23, 2024); the steam-terms, jobs, gandy-dancer, stations, and Class I rewrites on this site for terms those pages own; GCOR/NORAC restricted-speed language as commonly published; STB Class I/II/III revenue thresholds as used on the Class I hub (2025 reporting-year figures); and FRA hours-of-service practice as crews still describe it (12-hour cap). Photographs are from the American-Rails.com collection except as credited (Shaw; Nicas).