[en.train] vt [MF entrainer, fr. en- + trainer to draw, drag--more at train] (1568) 1: to draw along with or after oneself
2: to draw in and transport (as solid particles or gas) by the flow of a fluid
3: to incorporate (air bubbles) into concrete
4: to determine or modify the phase or period of "circadian rhythms ~ed by a light cycle" -- en.train.er n -- en.train.ment n
[2]entrain vt (1881): to put aboard a train ~ vi: to go aboard a train