Backlin巴克林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 knitted fabric双面针织物backscatter pattern后向散射图back ground current维弧电流backpressure rising背压升高back to back escrow[法] 背对背契据back-seated valve强迫就位阀,后座阀back-porch effect后沿效应back up water level回升水位backscattering wave反向散射波backing-off lathe铲齿车床,铲工车床