Word Origin & History
early 14c., "a drawing out, delay," later "trailing part of a skirt" (mid-15c.), also "retinue, procession" (mid-15c.), from O.Fr. train (fem. traine), from trainer "to pull, draw," from V.L. *traginare, extended from *tragere "to pull," back formation from tractus, pp. of L. trahere "to pull, draw"
(1)). Train of thought first attested 1650s. The railroad sense is recorded from 1824, from notion of a "train" of carriages. British train-spotting "hobby of observing trains and recording locomotive numbers" is recorded from 1958.
"instruct, discipline, teach," 1540s, from train
(n.), probably from earlier sense of "draw out and manipulate in order to bring to a desired form" (late 14c.). The meaning "to travel by railway" is recorded from 1856. Trainer is recorded from c.1600; trainee from 1841.