bottomed... 底的底是 ... 的bottomn.底部；底端adj.底部的v.触底；打(基础)bottom hole sampler井底取样器bottom water coning底水锥进bottom fired heater底烧炉bottom bearing beam下部承重梁bottom of the ninthn.九局下半；棒球比赛中第九局的下半局；是比赛的最后时刻bottomhole assembly井底动力钻具bottom bearing case底轴承盒bottom sketch plate中幅板bottom-up parsing自底向上句型分析bottom-out system末位淘汰制