0-9, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z, [Contents]

J door
The door between the cab and saloon.
Warrant: LUL Jargon Buster
Plural form: J doors

CL Vehicles and vehicle components
BT vehicle door

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jack
A device for lifting heavy objects.
Literary warrant required.
Plural form: jacks

CL Tools and equipment
BT breakdown equipment
NT bell jack
NT bottle jack
NT hydraulic jack

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jack shaft
Any of various kinds of auxiliary or intermediate shafts which are driven by another shaft or by a set of gears and form part of the drive train between engine or motor and driving wheels.
Warrant: Electric Locomotives and Railways, H Greenly, no date p246
Plural form: jack shafts

CL Vehicles and vehicle components
BT <power transmission components>

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jet powered locomotive
A locomotive driven by a gas turbine, or jet engine driving a generator.
Literary warrant required.
Plural form: jet powered locomotives

CL Vehicles and vehicle components
BT <locomotives by power source>

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jim crow
A manual tool used for bending rails.
Warrant: The Railway Dictionary, An A-Z of Railway Terminology, Alan A Jackson, Alan Sutton Publishing, 1996
Plural form: jim crows

CL Tools and equipment
BT gangers equipment

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jimmy
A piece of metal illegally placed in a blast pipe of a steam locomotive to split the blast thereby increasing the draught and obtain better steaming.
Warrant: The Railway Dictionary, An A-Z of Railway Terminology, Alan A Jackson, Alan Sutton Publishing, 1996
Plural form: jimmies

USE blast pipe jimmy
CL Tools and equipment
BT drivers equipment

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jinty
The nickname for a 6 wheel side tank locomotive designed for shunting and light freight duties designed by Sir Henry Fowler.
Warrant: The Observer's Book of Railway Locomotives of Britain, Frederick Warne & Co. Ltd
Plural form: jinties

CL Vehicles and vehicle components
BT six coupled locomotive

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Johnson coupling sleeve profile
Scope note required.
Literary warrant required.
Plural form: Johnson coupling sleeve profiles

CL Unidentified
BT <unidentified terms>

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joint stock railway
A railway owned by a joint stock company (i.e. a company of shareholders).
Literary warrant required.
Plural form: joint stock railways

CL Railway types
BT <railways by ownership/funding>
NT contractors line

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jointed track
Normal track constructed of rails in lengths of 60ft or less (i.e. not welded).
Warrant: Railtrack Jargon Buster, 1999
Plural form: jointed tracks

CL Track and track components
BT <track by jointing>

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jointless track circuit
A track circuit which does not require insulated rail joints at its extremities.
Warrant: The History & Development of Railway Signalling in the British Isles, Friends of the National Railway Museum
Plural form: jointless track circuits

CL Control and communications
BT track circuit

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journal (axle component)
The part of a shaft or axle which rests on the bearings. In the case of railway vehicles, the part of an axle inside the axle box.
Warrant: The Railway Dictionary, An A-Z of Railway Terminology, Alan A Jackson, Alan Sutton Publishing, 1996
Plural form: journals

CL Vehicles and vehicle components
BT <wheel assemblies>

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Joys valve gear
A steam locomotive valve gear which derives its movement from the locomotive connecting rod.
Warrant: Developments in Locomotive Practice, Bowen Cooke, 1910
Plural form: Joys valve gear

CL Vehicles and vehicle components
BT valve gear

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jubilee track
Temporary track laid by the contractor during the building of a railway or other civil engineering or construction enterprise.
Literary warrant required.
Plural form: jubilee track

USE temporary track
CL Track and track components
BT <track by permanence>

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jumper
An overhead trolley lead for moving electric cars inside a depot.
Warrant: The Railway Dictionary, An A-Z of Railway Terminology, Alan A Jackson, Alan Sutton Publishing, 1996
Plural form: jumpers

CL Built works and components
BT <electricity supply components>

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jumper head
The coupling socket provided at the end of a jumper.
Warrant: Railway Technical Web Pages, Piers Connor, 2000
Plural form: jumper heads

CL Built works and components
BT <electricity supply components>

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jumper lead
A multi-core cable used to provide electrical connections between railway vehicles.
Warrant: Lexique General de Termes Ferroviares, Union Internationale des Chemins de Fer, 1975
Plural form: jumper leads

CL Vehicles and vehicle components
BT <secondary electrical circuitry>

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junction
Scope note required.
Literary warrant required.
Plural form: junctions

CL Built works and components
BT <junctions and crossings>
NT burrowing junction
NT flat junction
NT flying junction

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junction indicator
An indicator provided at a junction signal to inform the driver which way a junction is set, by means of a line of white lights.
Warrant: The History & Development of Railway Signalling in the British Isles, Friends of the National Railway Museum
Plural form: junction indicators

USE position light junction indicator
CL Control and communications
BT route indicator

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junction signal
Any signal that has more than one running route and is capable of displaying an indication of route.
Warrant: The History & Development of Railway Signalling in the British Isles, Friends of the National Railway Museum
Plural form: junction signals

CL Control and communications
BT directing signal
RT splitting distant signal

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junction trackwork
An assemblage of turnouts, diamond crossings, etc. forming a junction between two routes.
Literary warrant required.
Plural form: junction trackwork

CL Track and track components
BT trackwork
NT ladder junction

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<junctions and crossings>
Points where the railway converges with or passes over other lines on the same level. Warrant: Railway Terminology Working Group
Plural form: <junctions and crossings>

CL Built works and components
BT <route complexes>
NT flat crossing
NT junction

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0-9, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z, [Contents]