Unno云野UNabbr.(=United Nations) 联合国pron.<口>人，事物，家伙，东西unmodified enzyme未修饰酶undetfeed burning下给料式燃烧unget-at-ableadj.达不到的；得不到的unbonded material无黏结材料undefended spaces鼻中隔膜部uncontrolled zone未控区间unbalanced factor不平衡系数unbonded coatings未粘合被复层ungraded position未定级职位uncommitted order未承诺的订单