The part of the track, often wood or concrete, where the rails are spiked or otherwise fastened.

one of the cross braces that support the rails on a railway track; "the British call a railroad tie a sleeper"

A piece of industrial lumber used to support rails on a roadbed. In Britain and other countries, a "Sleeper".

Black, tar and preservative impregnated, 6" X 8" and 6'-8' long wooden timber that was used to hold railroad track in place; normally used as a member of a retaining wall

A timber support for railroad tracks.

A railroad tie, cross tie, or sleeper is a rectangular object used as a base for railroad tracks. Sleepers are members generally laid transverse to the rails, on which the rails are supported and fixed, to transfer the loads from rails to the ballast and sub grade below, and to hold the rails to the correct gauge.