backman辅助工backn.后面；背脊；靠背；后背；后卫vt.支持；后退adv.向后地adj.向后的；后面的；偏远的；过时的；积欠的back-space editing capability倒带编辑能力back-scattered form functions背向散射形函数back-to-back duplex bearing成对双联轴承back and forth turning movement进退转身back connection type instrument背面连接式仪器backpressure extraction turbine背压抽气式汽轮机Backstroke turn to breaststroke仰泳转蛙泳Backing up to network drives.备份到网络驱动器。back electromotive force method反电动势法backed-up value in game trees博弈树中折返值