Jargon and Technical Terms - II

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For technical terms starting from A and until N, please refer to this page.

Glossary of Technical Terms in English: M – Z

Mail train
For this and related terms see the section on operations.
Main line
Refers to the tracks used for the main running line or for long-distance trains; the relief line or local line refers to any other tracks that run parallel to the main line tracks but are used for local passenger trains, suburban trains and similar traffic.
Major bridge
A bridge that spans a gap of more than 18m, or has an opening between pillars of over 12m.
Make-up time, margin, recovery time
See the section on operations
Marshalling yard
A yard where rakes (consists) for various trains are assembled and disassembled as required; typically contains a huge maze of highly interconnected sidings and tracks, lots of coaches, wagons, tankers, etc. being shuffled around to put together in formations as required, and equipped with lots of shunter locos. (US: 'classification yard')
Master controller
A lever, handle, or wheel control in a locomotive that can be moved to different positions to set the configuration of the traction motors and controlling circuits and thereby control the speed of the loco.
Material train
A departmental train carrying equipment or material, such as ballast, for railway works.
Maximum permissible speed(MPS)
See the items related to working timetable and scheduling in the section on operations.
A large-scale traffic block for engineering work or other reasons. See the section on operations for more on different kinds of blocks.
Mixed train
A train that carries both passengers and freight (goods or animals). Often, such a train has a rake that is mostly composed of passenger stock, with perhaps one or two freight cars attached at the front (less often, at the rear).
Monomotor bogie
Refers to a bogie where one traction motor drives both powered axles of the bogie. Derived from the term monomoteur in French.
Monsoon load
The maximum load for a particular combination of motive power in the rainy season (when tractive effort is reduced because of the wet conditions).
A term occasionally used for diesels operating lashed up as multiple units.
Net load
Refers to the total tonnage of goods or passengers being carried in a wagon or coach or in an entire train.
Neutral section
Also known as dead zone. Refers to a section of catenary that is not energized. It isolates successive sections of different phases or voltages. A dynamic neutral section is one that can be switched from one traction supply to another, e.g., DC to AC. See the section on electric traction for more information.
Neutral temperature
The stress-free temperature for destressed and pretensioned continuously welded track.
Nil caution
A caution order issued by a notice station indicating no special restrictions to be observed between that station and the next notice station.
No Road
See Two Road.
Nose-suspended, or axle-suspended motors are those that are suspended directly from the axle and not from the frame of the bogie (contrast frame-mounted).
One of the several available settings in controlling the speed / power / torque of the traction motors of a locomotives. A typical locomotive may have about 30 or so notches. In locos using tap-changers, the notches correspond to the taps. Notching up refers to stepping up through these notches as the loco accelerates; similarly notching down for deceleration. In some locos, some notch positions cannot be sustained for long periods of time, whereas a few can be held indefinitely; these latter are then known as free notches. See the section on electric traction. Also see progression and regression, and vernier controller.
Notice station
One of the stations on a route issuing divisional caution orders for that route (in addition to the station adjacent to the block section which requires the caution order).
Refers to any train, vehicle, or obstacle that is on a section of track or fouling it, so as to present a danger to trains that might run on that track.
Occupancy chart
The Occupancy chart for a station details which platforms and sidings are occupied, and by which trains, at different times. Sometimes the term occupation chart is used.
A common term for the numeral zero in spoken IR lingo. For example, '0/9' is pronounced 'odd bar nine'.
To officiate over a train, said of a driver, is to be assigned to a train.
On line
Bringing, or putting, something on line refers to bringing it into service or commissioning it. Used of new models of locomotives or coaches, etc.
Onward journey
An intermediate section of a trip
Operating number
A locomotive's serial number as allotted by the railway.Contrast with construction number.
Operating ratio
(For a railway) The ratio of operational expenses and payments to gross earnings.
An ordinary train is one that is not a mail or express train (also known as just a passenger).
In contrast to the meaning in other contexts, refers to the availability of locos for traffic use from a shed. More precisely, it is the average number of locomotives that are in working condition and 'outside' the shed (i.e., in productive use for hauling traffic), sampled periodically, and quoted as a percentage of the total number of locomotives homed at the shed. The higher the outage figure, the better the performance of the shed. The sampling may be hourly or less often; it was every 4 hours for steam locos.
A Railway Out-Agency (or Out Agency) is an organization that has made arrangements with IR to provide connecting road services to passengers from certain stations to nearby towns; these agencies can also issue combined road-rail tickets to passengers for such journeys.
(For ticketing purposes) means a station other than where the ticketing is done: the destination, normally, or the starting point when purchasing reverse journey tickets. Also refers to any station other than a crew's home station, where train crew may stay for a while.
Out time
The actual departure time of a train from the originating station, as recorded in the train report.
Structure on top of an electric locomotive used for collecting electric current from the overhead catenary.
Party ticket
A ticket issued for several persons travelling as a group (usually in special categories, e.g. educational tours).
Passenger train
See the section on operations.
Passenger fit
An annotation used for some locomotives (mostly WDM-2's) that have been certified for use with mail/express train hauling and are earmarked for those (and not to be used with goods trains). There are also some locos marked passenger train only which are used only with slow passenger trains and not with mail/express trains running at higher speeds.
A member of the permanent way inspection staff who is charged with walking along the track to visually inspect it. A patrol refers to a complete inspection trip (out and back) made by a patrolman.
Phase gap
The discontinuity in the electrical supply to the OHE at the boundary where different sections of the catenary are supplied by different phases from the local power supply station. Also phase break.
A pilot, or shunting pilot, or station pilot is a shunting locomotive used at a station for handling the chores of switching sectional carriages around, forming rakes for passenger trains, etc. (This was more prevalent in steam days as the main locomotive for hauling a passenger train would be getting coaled and watered at the time that the pilot was putting together the rake it had to haul. An up pilot handles trains from the Up direction; similarly down pilot. The term is also used to refer to the driver of such a shunting loco.
Pilot loco
An additional loco attached at the front of a train (in contrast to bankers that are usually attached at the rear to help push up a train on inclines). Sometimes loosely used for pilot train.
Pilot train
A pilot train (also sometimes loosely called pilot loco) is a train (often a light loco, or a loco with a wagon or two in front of it) sent ahead of another train to check for problems with the tracks, and bridges, looking for damage or sabotage, etc. The pilot train usually runs one block section ahead of the train it is protecting. This practice is prevalent for guarding trains carrying VIPs; and also for guarding all trains in in areas where terrorist groups are active and have targeted railway infrastructure. An empty flatcar or other wagon is often attached in front of the pilot train's locomotive so that it can trigger any explosive devices, or bring out any problems with the track before the loco itself reaches the spot.
Platinum Pass
A pass that provided unlimited free travel on IR for current and past Railway Board members and their friends and family, by air-conditioned first-class. It was instituted in 1997 by the Railway Board and withdrawn soon thereafter by order of the Delhi High Court following a successful public-interest lawsuit. The plaintiff had argued that such a generous perquisite was inappropriate given that the ordinary public could hardly get reserved accommodation on most trains.
A plinthed locomotive is one that has been placed (usually after restoration or preservation work) on a short section of track on a platform, yard, station forecourt or anywhere else where it is no longer connected to active running lines. A list of plinthed locos in India is in the section on locomotives.
These are the same as in UK usage: equivalent to a 'switch' in US usage. Facing points are points that control diverging routes (from the point of view of the train's direction of motion). Trailing points control converging routes (again with respect to the direction of motion of the train). If access to a siding is provided only by trailing points, the train must pass over the points and then reverse to be diverted on to the siding.
Point rail
Term for a 'point' in US usage: the actual tapered rail or tongue rail that moves and abuts a rail to cause the wheels to be deflected off on to the other track.
Pink Book
IR's annual compendium of Works, Rolling Stock, and Machinery & Plant programs, detailing allocations from the capital expenditure for the year; the Blue Book is a similar compilation detailing revenue expenditure allocations.
A power is a locomotive. A dead power is a nonfunctional locomotive that has to be hauled away for repairs. An unbalanced power refers to a (steam) loco with broken or damaged side rods which can still be driven but only slowly. A power failure is a breakdown of a locomotive.
Power plan
The schedule of all up and down trains from a station and expected locomotive and crew requirements for them, used to determine actual locomotive and staff allocations.
This word is not really an IR-specific one but is widely encountered in Indian English. To prepone something is to advance its scheduled occurrence and is the opposite of 'postpone'.
Private handle
A dual spanner that can be used to operate the Master Conroller as well as the Brake Controller in an EMU or locomotive, but without the mechanical interlocking provided by the spanners normally used to operate these controls. This allows use of either or both controls while at the same time allowing the spanner to be removed from the control panel (and returned to the motorman's pocket).
Private number
A number that is provided by a station master to a signal cabin or level crossing gateman when some action is to be taken, such as pulling off a signal to accept a train, or to open or close the level crossing gates. The person performing the action notes the number down in his records as proof that the action was authorized. The numbers are not in a sequence, and are made up by the station master or his deputy in some way known only to them, so that there is little chance of anyone guessing a private number for the purpose of covering up an unauthorized action.
Term used to refer to the sequence of steps or notches on the master controller through which a locomotive is taken when increasing speed; regression is the term used for the sequence when slowing down. Also see auto-regression.
Term used for the connecting train which a driver is supposed to take back to his home station after having driven a train out of the home station.
Proportioning valve
A valve found on most recent models of locos that allows the loco brakes to be applied automatically when the train brakes are applied, to increase the braking power. Older locos such as the WCM-1 and WCM-2 lacked this valve, making their train brakes and loco brakes truly independent in application.
Punctuality as a figure (e.g., 90%) is measured as the fraction of trains that arrive and depart within a certain threshold of the scheduled time (e.g., within 15 minutes), at stations in a particular division or zone over a period of time.
This type of operation refers to a train set up so that the locomotive is not moved around when the train has to reverse direction — the locomotive stays in the same position, and either pushes or pulls the train as appropriate. Of course, when the loco is at the rear of the train, a driving cab must be used at the other end. Sometimes there may be two locos, one at either end; one pushes and the other pulls in one direction, and the roles are reversed for the return trip. A twist on it in IR is that an arrangement where a single loco in the middle of the rake provides the motive power, with unpowered driving cabs at either end of the rake, is also known as a push-pull.
Python rake
An informal term used by some on NR / NER to describe a freight rake that is composed of two or three other rakes (sometimes including their locomotives) that are simply marshalled together to form one rake for the shared part of their journeys. At an intermediate point the constituent rakes are uncoupled and go their own ways.
Quick Transit
A class of freight service providing faster delivery times than normal.
Quill drive
A method of connecting a traction motor to the axle of a bogie by means of a hollow tube (the quill) around the axle.
The number of seats or berths earmarked for a particular category of passengers. Most often refers to the seats/berths set aside for passengers entraining at an intermediate station. (referred to as the quota for that station). This was essential in the days before computerized reservations, for controlling the number of tickets issued at intermediate stations.
Return journey quota is the number of seats/berths on a train for which tickets can be issued by a station for a journey terminating at that station. Tourist quota : for tourists paying in US dollars or other foreign currency. Similarly, senior citizens quota, VIP quota, emergency quota, etc. General quota refers to the generally allocatable seats/berths that don't fall into any of the above quotas. Pooled quota refers to the quota for several stations that has been combined following the introduction of networked computerized ticketing.
Trade name for a brand of bottled drinking water marketed by IR.
Railway Board train (RB train)
Also known as a board-monitored train) this is any of a few selected trains chosen for political or other reasons and given high operational priority and therefore tending to be very punctual (on-time running for a division or zone may be measured by these trains). Delays in such a train's running are promptly reported to the Chief Operations Manager of the division concerned, as are complaints regarding cleanliness, security, and passenger amenities. A railway minister's train is one of the trains that is given even higher operational priority because it enjoys the position of being personally supervised by the Minister for Railways or other such high official (also termed being on the MR list). Many important trains such as the Tamil Nadu Exp., Rajdhani Expresses, Shatabdi Expresses, and others are board-monitored.
A formation of coupled coaches or cars that makes up a train (minus the loco) is called a rake; the same as a 'consist' or 'cut' of cars in US terminology. (The word formation is also sometimes used in IR parlance for a freshly assembled rake.) Note that the word 'rake' is often pronounced 'rack', especially by non-English-speaking railway staff; this has sometimes also led to the erroneous spelling 'rack' in printed text.
Rake link
A detailed description of the rake compositions and movements for various trains handled by a particular division or zone. It usually covers the movement of stock for about 2500km (the primary maintenance period). Similarly, there is an engine link or loco link detailing movements and allotments of locomotives. See the section on operations.
Raksha Dhaga
("Thread of Safety") is a safety arrangement used by KR to protect trains from the effects of landslides or rockfalls which are common in some sections. The arrangement consists of a trip wire that is suspended alongside the track at varying heights (at or above the height of a typical train). The wire is under tension by a hanging weight at one end. The other end terminates in a box that has a maintenance-free battery, a rotating beacon light, and a hooter horn. When the trip wire is suddenly subject to additional tension as would happen if a landslide resulted in rocks and debris falling on to the tracks from above, it activates the horn and beacon light to warn approaching trains of the hazard ahead.
Rationalized route
A pre-determined route between a pair of points that IR uses to compute freight charges for a shipment, regardless of whether the shipment actually uses that route or a different, possibly shorter (and cheaper) route.
Refuge siding
A siding fitted with catch points and interlocked with a running line. It purpose is to hold trains to allow faster or more important trains to pass it. These are often provided on ghat sections to allow passenger trains to overtake the heavy and slow goods trains.
To be regulated, said of a train, means that it is stopped at a certain point before its final destination because of weather, track problems, etc.
Relativity index
(For a particular class of travel and accommodation), , is the proportional factor applied to ordinary second-class fares to compute the base fares for that class. E.g., Sleeper class has a relativity index of 155% or 1.55, which means that the base fare for a ticket on this class is 1.55 times the fare for ordinary second-class travel. Sometimes the index is quoted as an amount, e.g., Rs 155 where it understood that the comparison is with Rs 100.
Reservation against cancellation (RAC)
Refers to a ticket with reserved (confirmed) sitting accommodations only, but whose status can change to providing reserved sleeping accommodations as well if enough persons holding reservations cancel their tickets.
General term for the opposing forces because of friction, air drag, etc. that have to be overcome by a locomotive to cause a train to move. Rolling resistance or running resistance is the term for the opposing force experienced when a train is in motion. Starting resistance is the term for opposing force that has to be overcome in order to get a train moving from a standstill.
Retiring room
A waiting room at a railway station, with facilities for overnight stay.
Return journey
A return journey ticket is the ticket for the second half of a round trip, or the final section of a circular journey. (See reverse journey.)
To reverse a locomotive is to detach it from one end of a rake and re-attach it to the other end.
Reverse curve
A section of track that has a curve in one direction followed immediately by a curve in the other direction (with or without an intervening straight).
Reverse journey (tickets)
Tickets that purchased for a trip from some other station to the station where the tickets are being purchased.
Reversing station
A point on a hilly railway route where a train can reverse and change direction by switching to another track, in places where the terrain makes it impossible to have a curve in the tracks; rather like switchbacks on mountain trails. Reversing stations in some cases have been replaced by newer track alignments that use tunnels and bridges built with technology not available in earlier decades.
Right time
Term used for the on-time departure or arrival of a train.
One of several tracks available for receiving trains at a station (usually leading to platforms).
Road learning
Refers to the trips undertaken by a driver in the cab of a loco driven by another driver, familiarizing himself with a new route that he is to drive on.
Road Station
A station that is accessible by road in addition to being served by the railway; a non-road station on the other hand is accessible only by rail.
Route kilometer
A unit of distance, measuring the distance by rail between two points on the railway network. See running track and total track kilometers below.
Running Room
A rest house for running crew (drivers/guards/TTEs) at a layover away from their headquarters (home base) station.
Running Time: Minimum Running Time, Normal Running Time
See the items related to working timetable and scheduling in the section on operations.
Running line
A line along with any connections that a train passes on when going through a station or between stations. I.e., sidings, branches, loops, etc. are not considered part of a running line.
Running track kilometers
The sum of all running lines (counting each line of doubled, tripled, etc., lines separately) between two points. See route kilometers and total track kilometers.
Running train
A train that has properly begun its journey (with authority to proceed) but which has not yet arrived at its next required halt.
Sand trap
Also called Sand drag. A short section of track that runs into a thick (several inches) bed of sand. It is used in conjunction with trap points; vehicles that move the wrong way on a siding will be diverted onto the trap and be derailed there instead of continuing on to the running line.
Scissors crossover
A pair of parallel or nearly parallel tracks with crossovers provided in both directions between the two lines (i.e., trains can be routed from either line to either line, in both directions). Often, scissors crossovers are provided from a running line to a dead-end siding to allow for one train to be passed by another. Also referred loosely, as scissors crossing
Seated load
The seating capacity (number of passengers for whom seating arrangements are provided) in a passenger coach or EMU. Also called sitting load
Security patrolling
Refers to patrolling track and visually inspecting its condition and checking for sabotage or damage by miscreants when there are civil disturbances in the area, or terrorist activity.
Certain kinds of express EMU services in Mumbai. See the section on operations.
Shaku couplers
(?) Local name for Scharfberg centre-buffer couplers used on EMUs and some locos (from the firm Scharfberg Kupplung GmbH, Germany). [Not entirely certain this is the origin of this term.]
A person who works under the direction of a turner (q.v.) to move shunting locos and others in and out of tight spots on shunting sidings, e.g., to allow the turner to move the main loco to some desired location. Shunter is also used to mean 'shunting locomotive'.
Shunting neck
Refers to the convergence of many tracks in a station or yard connecting within a very small stretch to the running line(s). Coaches may be shunted to and from the shunting tracks while breaking up and reforming rakes.
Shunting gear
The gearing of a shunting locomotive set when it is working with at low-speed on heavy-haul shunting duties.
Sick (coach)
A sick coach is one that is one that is in need of repairs or maintenance and withdrawn from service for that purpose.
Any track which is not a running line. This contrasts with US usage where a siding refers to passing lines or loop sidings only; in Indian usage it includes these as well as what are called side tracks in the US. A dead-end siding is a siding that is not a loop or passing line.
For all signal-related terms such as Distant, Warner, Outer, Home, Starter, Gate Stop, semaphore, colour-light, position-light, disc signal, banner signal, repeater, calling-on signal, co-acting signal, etc., please see the section on signalling. A fixed signal is a signal in a fixed location, as opposed to hand signals, temporary or emergency signals, etc. The last stop signal refers to the fixed stop signal which controls entry of trains into the next block section ahead. Similarly, the first stop signal controls the entry of trains from the previous block section.
Single line
A route where one set of tracks exists but trains may be routed over it in both directions (up and down); a twin single line is a route with two sets of tracks, where either line can be used for routing up or down trains. In contrast, with a double line normal working has one line reserved for up trains and the other for down trains.
A tie for the rails, or a car with sleeping accommodations.
A crossing of two (or more) railway tracks with points/frogs so that trains can move from one track to the other. A single slip is a slip which only allows trains from one track to cross over to the other (or to continue on the same track), but where trains on the other track cannot change over to the first. A double slip is a crossing of two tracks (at a small angle) with points/frogs that allow trains on either track to be routed on to either track.
Slip coach
See the section on operations for more on this and related terms.
Slip siding
This is a siding provided going off the main line away from a station, that prevents runaway trains that escape from the station limits or yard limits from continuing on the main line. Normally the points are set to divert all trains to the slip siding, so only authorized trains can proceed on to the main line. Slip sidings are usually provided to the rear of the last stop signal of any line leading out of the station or yard. Slip sidings are also provided to protect trains from collisions at cross-over points on single lines. See also catch siding.
Goods consigments of small dimensions, many of which can be sent together in one parcel van or freight wagon, as opposed to larger goods items that often require the exclusive use of an entire wagon.
An extra train not found in the normal timetable. Also termed a holiday special if it's a train intended to ease traffic during vacation or festival times. A trial special is a special train used for carrying out a trail run (line trials, oscillation trials, etc.) with new or experimental rolling stock. The first official run of a new train or new locomotive is often designated an inaugural special. (Loosely similar to: US: 'Extra'; UK: 'Special Traffic Notice').
Splitting a switch
Also known as a trail-through -- this refers to the case where a train moves over trailing points that are accidentally set for a loop line, thus forcibly pushing apart the rails at the points.
On severe inclines, it is not sufficient to depend on the parking brakes of coaches or wagons to keep them stabled or parked. Sprags are metal (steel) bars that are inserted between the spokes of a wagon's wheels to prevent it from rolling away; scotch blocks or stop blocks are wooden or metal wedges that are placed on the rail under a wheel for the same purpose. Also called scotch blocks / stop blocks
Stabling shed
A shed where a loco may make a short stopover in between trips, etc. A stabling yard is one where rakes are stored (usually without any maintenance) away from the home yard, before they are assigned to the next train service.
Staff magazine
Not be mistaken as a periodical publication for the employees! It is the holder for the staffs used by an electric staff block instrument (e.g., Webb & Thompson).
Standing load
Refers to the total number of seated and standing passengers a regular coach or EMU car (or buses, in other contexts) is designed to carry under normal conditions. Full standing load is another term sometimes used: the number of passengers at which more passengers decide not to enter the coach (non-rush-hour).
Starting journey
The first section of the trip commencing from the originating station.
Stop collar
A small ring, sleeve, or tag attached to a point lever as a reminder that the points (and signals) controlled by that lever if interlocked) have been set to protect a train on that section -- so that the section is not cleared for another train by mistake. Often the collar also interlocks mechanically so that the lever cannot be moved while the collar is in place.
Straight coupler
The same as the standard CBC coupler used on IR. Also known as a non-transition coupler. In contrast, transition couplers have a CBC arrangement and also a mechanism to link to screw couplers.
The layer of material (mostly soil) provided above the subsoil, and below the ballast layer or the blanket of a track formation if a blanket layer is provided.
The soil of the natural ground below the subgrade layer of a track formation.
A superfast train (see below); usage among some IR staff.
The section on operations has more information on this.
Support Wagon
A wagon or tanker filled with an inert cargo (sand, water, etc.) coupled at either end of a freight rake of hazardous or inflammable material (e.g., petroleum products) to protect the cargo in the case of a collision.
Suri transmission
An indigenous version of a hydraulic transmission with lock-in torque converter to provide rigid mechanical coupling at speed to reduce transmission losses. It was invented by Mr M M Suri at RDSO in 1956 and was incorporated in a number of diesel locomotives.
A facility where reserved tickets with confirmed sleeping accommodations can be obtained one day in advance of the journey on payment of a premium, even if the normal reservation quotas are exhausted.
Squads of about 4 to 6 women officers (ticket examiners and police constables) that conduct checks for ticketless passengers in the ladies' coaches of Mumbai suburban trains and elsewhere.
Telescopic fares
IR's fares do not increase proportionately with distance & for longer journeys, the fare per unit distance is lower than for shorter distances, and keeps falling in slabs as the length of the journey increases. For this reason they are sometimes described as telescopic.
Track Formation
This term includes the entire permanent way structure including the track foundation (see below) and the rails and sleepers themselves.
Track Foundation
This term includes the ballast, blanket, and subgrade layers of a track formation, which are placed to transmit the load of the trains to the subsoil.
Track kilometers
(Or total track kilometers). Includes the sum total of all running lines and sidings, yard trackage, etc., between two points. See route kilometers and running track kilometers.
General term for any trains moving on the tracks. Revenue traffic (or revenue-earning traffic) consists of traffic for which IR is paid, as opposed to departmental traffic (see departmental) or non-revenue traffic which is traffic that is conveyed free of charge by IR. Goods traffic is measured in net tonne-kilometers (NTKM) -- the conveyance of 1 tonne of goods over 1km, or gross tonne-kilometers (GTKM), where the weight includes the weight of the vehicles and locomotives.
Another measure commonly encountered is loaded wagon-kilometer representing the conveyance of a full goods wagon over a distance of 1km. Passenger traffic is naturally measured in passenger kilometers. Another unit sometimes encountered is the train kilometer, representing the movement of a train over 1km. Similarly, one also finds engine kilometer, representing the movement of a locomotive over 1km under its own power.
Traffic density
Amount of traffic (usually taken as an annual figure and measured in NTKM or GTKM or passenger-kilometers) per unit measure of track, either route km or running track km.
Train Examiner
IR staff person who inspects a train and certifies that it is fit and safe for running.
Technical halt
A halt which is present only for purposes such as loco crew change, loco change, water pick-up, cafeteria supplies pick-up, etc. It is not a halt meant for passengers to embark or disembark, and it will often not appear in the passenger timetables at all (it of course does show up in the working timetables used by the crew).
Terminal capacity
the maximum number of trains that can be handled in a day (24 hours) by a yard.
Testing train
A train (usually just a loco with one or two empty coaches) that is used to check newly constructed or repaired permanent way for adequate clearances for the loading gauge, speed trials, etc.
Through carriage
Refer to the section on operations.
(For a section) The amount of traffic that can be carried in that section in a day (24 hours), measured in the number of wagons, coaches, tonnne-km, or passenger-km.
See the entry for berth. Often mispronounced as though it were 'tire'.
See the entry for splitting a switch.
Train care centre
(Or a coaching depot) is the part of a station or yard that handles stabled passenger rakes and prepares them for service (cleaning, maintenance, etc.).
Tractive effort
See the section on locomotives.
Trap points
Also known as derailing points (or a derailing switch), are like catch points except that they do not lead to a corresponding catch siding but instead are normally set to cause any vehicle moving over them to be derailed immediately or on to a sand trap. They are used on sidings or branches where a wrong movement of any vehicle would lead it on to a running line (a low-speed derailment in this case is preferable to a collision with a high-speed train on the running line). (Similar to a 'derail' in US usage.) A trap indicator is a signal that indicates the setting of trap points.
The same as a 'wye' in US parlance — three connected sections of track (in a triangular configuration) that allow a loco to be reversed in direction.
Turnaround time
The turnaround time (or just turnaround) for a wagon is the round-trip time for the wagon between two loadings.
A junior driver who assists in moving locos around the yard (in steam days, the one who assisted with turning locos on turntables or at triangles).
A section of track branching off from another. Sometimes spelled 'turn-out' or 'T/out'. Occasionally for turnouts the deflection is also specified by a notation such as '1 in 8.5', which refers to the amount of deviation from the straight line track.
Twilight Switch
A relay with a photovoltaic cell which turns the lamp of a semaphore signal on or off depending on the ambient light; usually provided along with solar panel and battery systems for semaphore signals.
Two Road
Also known as no road, this is what happens when facing points happen to be left in an intermediate position between being set for the main line or the loop line -- in this case, wheels on one side of the train follow one route and the wheels on the other side follow the other route, until of course the train derails when the distance between the rails becomes too large.
(Informal) Term used in the Chennai area for local suburban trains (especially earlier for the MG services). In contrast to engine local, q.v.
Universal number
4-digit train number for a long-distance train, unique across the zones, as introduced in the train renumbering of 1989.
Unstable Formation
Refers to track formation (see above) which yields or deforms continuously without settling into a final shape, or which repeatedly experiences slope failures necessitating frequent maintenance.
A wagon is freight car. Wagons make up goods stock, q.v.. Contrast with vehicle. A unit wagon is a rigid (non-bogie stock) 4-wheeled freight car. Contrast with bogie stock.
Wagon interchange
Refers to the controlled movement of wagons between the zonal railways in order to maintain a generally balanced allocation of wagons among the zonal railways. Wagon interchange points (47 or more of these exist) are places where such exchanges occur. E.g., at Mughalsarai ER and NR exchange 4,500 to 5,000 wagons each day.
Waitlisted (ticket)
A waitlisted ticket is one issued without a firm reservation, but whose status will change to fully reserved if enough persons holding reservations cancel their tickets. Unlike RAC tickets, waitlisted tickets do not guarantee even sitting accommodation. A waitlist number indicates your sequence position among all those who have waitlisted tickets for a particular train. The running waitlist number is the identifying number to be used in enquiries about the status of a ticket, while the current waitlist number is the sequence position among those who have waitlisted tickets, at the time that the ticket was issued.
Ward car
A special car with medical facilities for carrying injured persons, usually attached to military trains or relief trains helping out at disaster locations.
Working timetable
The timetable used by railway staff. It includes information beyond the schedule information shown in commercial timetables. The additional information relates to operational details, such as speed restrictions on various sections, crossing times for trains, the amount of make-up time allotted to trains, permissible speeds, operational rules (lengths of rakes that can be hauled by various locos, banker rules, special rules in force at particular stations), etc. See the section on operations.
The term refers to any passenger coach, saloon, guard van, railcar, or any other such stock for carrying passengers or staff and not freight. Vehicles make up coaching stock, q.v. Vehicles carrying passengers are termed passenger coaching vehicles (PCV) and all others are termed other coaching vehicles (OCV).
Via Bhatinda
An unofficial term in use in earlier decades and especially in pre-Independence times, to refer to someone who had risen through the officer ranks of a railway solely by connections and nepotism. The origin of this term is unclear.
Vernier controller
(Also known as vernier handle) is an additional subsidiary control in the form of a lever, wheel, etc. (e.g., it may be a control coaxially placed with the master controller) which provides for finer gradations of control within the main sequence of notches or configurations that the master controller provides.
Vice First Class
A curious IR term for any second-class sitting or sleeper coach pressed into service instead of a first-class coach, if the latter is not available for some reason. Sometimes these coaches are more or less permanently set aside for use as first-class substitutes, with 'vice first class' marked on them.
Vulnerable point
A vulnerable point may not refer to points at all, but is any location along the track where there is a danger of track defects developing, for instance by subsidence or shifting of the track bed, flooding, problems with the ballasting, etc.

Glossary of Terms in Indian Languages

Terms in Hindi

Note: Although these are classified here as Hindi terms, some (not all!) of these are widely used or understood in many areas of India.

A passenger car (coach).
'Maal Gaadi'
A freight (goods) train.
The tracks
Electric traction
(Bombay division) A driver.
(Also anglicized as "Augwala") literally fireman, but generally used for the assistant driver even today.
'Chhoti rel'
(Colloquial) MG or NG (literally, "small rail")
Permanent-way worker or gangman. (Literally this means '12-monther', referring to the nature of gangman's job which requires going out at all times and in all kinds of conditions.)
A mixed-language term; 'bada' = big in Hindi. See the section on operations.
'Half', a local term for the short 4-coach passenger train that used to run between Rewari and Ringus in the 1970s; also applied to some other short trains in northern India.

The following are “official terms” used in Hindi translations by IR.

'Shayan yaan'
Sleeper coach
'Paryatan yaan'
Tourist coach
'Vatanukool kursi yaan'
AC Chair Car
'Vatanukool shayan yaan'
AC Sleeper car
'Prasheetit yaan'
Refrigerated van
'Rasoi yaan'
Pantry car
'Upari upaskar'
Assistant Driver
Guard (??)
Carrying capacity (weight)
'Samay sarrani'
'Shramik Gari'
Departmental train for staff
'Satarkata Aadesh'
Caution Order