railroad tie

cement or wooden beam that is used as a base for railroad tracks

"Cross tie" redirects here. For the song "Cross Tie" by Avail, see Over the James A railroad tie, cross tie, or railway 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.
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Noun
1. one of the cross braces that support the rails on a railway track; "the British call a railroad tie a sleeper"
(synonym) tie, crosstie, sleeper
(hypernym) brace, bracing
(part-holonym) railroad track, railroad, railway