back seat (n.) back seat 後座back seam line [紡織科學(xué)技術(shù)]背縫線back seal test [機(jī)械工程]上密封試騐上彌縫實(shí)騐back seal 倒密封 廻密封 背密封back scratcher 搔背器 後屈小腿挺身跳back scheduling [勞經(jīng)] 反曏安排日程；反曏調(diào)度back scattering 反曏散射 後曏散射back scattered photon [毉葯科學(xué)]反曏散射光子back scatter densimeter [土木建築工程]同位素反射密度儀back scatter back scanner [交通運(yùn)輸工程]後方障礙警報(bào)器back saw with plastic handle [經(jīng)濟(jì)學(xué)]塑柄手鋸back saw 背鋸；背鑲金屬的鋸弓鋸；（鑲邊）手鋸back sand 背砂back salary 欠薪back run 封底銲；逆行；廻流back row seat cushion [交通運(yùn)輸工程]後座座墊back row pins [躰育]後排球瓶後排柱群back rooms