unaun.[动]二趾树懒unaabbr.(英国)联合国协会(=United Nations Association)Una.n.尤娜(女子名)unapproved part非法的零备件unattended radar无人值守雷达unabsorbed costs[经] 未分配成本unannounced quiz临时测验unadjusted index未调整指数unauthorized use违令使用unaerated lagoon非曝气塘unattractivenessn.不引人注意unattended woman孤身女子Unattended girls农村留守女童