bottomryn.船舶抵押契约；冒险贷借bottomn.底部；底端adj.底部的v.触底；打(基础)bottom protection护底bottom-gate TFT底栅薄膜晶体管bottom pit shield基坑支护bottom transverse船底横向构件,船底横材,底部横材bottom dump truck底卸卡车,底部卸料车Bottom Experience底层经验bottom end bearing连杆大头轴承bottom board slope底板坡度bottom dump bucket底卸式铲斗,底卸料斗Bottom Bouncetrack海底反射跟踪