backemfn.反电动势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-to back credit[法] 背对背信用状, 对开信用状back-pressure curve回压曲线back scattering ratio反(向)散射率back pack transmitter背负式发射机Back-striped weaseln.背纹鼬back - edge cutting螺旋桨切边back scatter constant[医] 反向散射常数backfilled regulation回填规则Back to the Holy Landbackscattering effect反射层效应