undercoat

n 1 [U, C] (paint used for making a) layer of paint under a finishing coat 底层（涂料）. Cf 参看 topcoat (top1). 2 [U] (US) = underseal.

under arms, under control, under the charge of, under the heel of, under the order of, under way, under-, under-secretary, under-sexed, under-side, underachieve, underachiever, underact, underarm, underbelly, underbid, underbrush, undercarriage, undercharge, underclothes, undercover, undercurrent, undercut, underdeveloped, underdog, underdone, underestimate, underexpose, underexposure, underfed, underfelt, underfloor, underfoot, undergarment, undergird, undergo, undergraduate, underground, undergrowth, underhand,