undwadj.水下的UNabbr.(=United Nations) 联合国pron.<口>人，事物，家伙，东西uncoiling angle开卷角unearned incomen.非劳动所得；非工薪收入undirected tree不定向树,双向树,不定向树无向树unrolled stator展开的定子unforced errors非受迫性失误unplanned blast无计划休风ungroup objects取消对象组unbiassed error无偏误差undulating wall波浪形墙体unmodified malt未降解的麦芽