U
U.I.C.	European Rail Association
UMLER	Universal Machine Language Equipment Register. Computerized database of information on every railroad car in service. This can be found at http://www.railinc.com/index.cfm
Uncle Sam	Railway Post Office clerk.
Uncoupling lever	Also called a cut lever. The device which raises the locking pin in a coupler to allow the knuckle to open for uncoupling.
Under The Table	Just as a man who "can't take his liquor" is sometimes actually under the table, so, figuratively, is a telegraph operator when messages are being sent to him faster than he can receive.
Underframe	Framework or structure which supports the body of a rail car.
Undergrade Bridge	(UG) Any point where the trackage crosses above any railroad, automotive, or pedestrian right of way, or stream.
Underground Hog	Chief engineer.
Undesired Emergency	(UDE) An undesired emergency application of a train's air brake system. (Also known as "Dynamiter" or "Kicker".)
Unit	A single locomotive or two or more locomotives that are coupled together and operated by one engineer.
Unit Train	A freight train consisting of one type of freight car, usually hopper cars for carrying coal or grain. Unit trains are seldom, broken up, and tend to operate continuously from loading to unloading point.
Unload	Get off train hurriedly.
Up-Line	Line over which trains normally travel towards the headquarters of the railway company.
Up-Train	One which travels on or in the direction of the up line.
Upper-Quadrant Semaphore	Signals whose blade extend upward from the lightbox to show “clear.”
USRA	United States Railway Administration. The USRA took over and operated American Railroads during World War I. It was responsible for certain long lasting and "standard" locomotive designs.
UTU	United Transportation Union. Labor union headquartered in Cleveland, Ohio representing railroad, bus, and mass transit workers in the United States and Canada.