oak 橡木 object 物体 observation cab 观光轿厢 observation lift 观光电梯 observatory lift 观光电梯 occupancy 占用,居住 occupant 占用者,居住者 occupants of building 大楼居住者,大楼住户 off peak 非高峰的,峰值外的 off position 断开位置 office building 办公大楼 off-peak traffic 非高峰交通状态 ohmmeter 欧姆计 oil 油 oil brake 油压制动器 oil buffer 油压缓冲器,耗能型缓冲器 oil buffer switch 油压缓冲器开关 oil can 油壶 oil collector 集油器 oil cooler 油冷却器 oil deflector 挡油圈 oil dish 积油盘 oil drip pan 接油盘 oil filler pipe 充油管 oil film 油膜 oil filter 滤油器 oil gauge 油量表 oil immersed transformer 油浸式变压器 oil leakage 漏油 oil level 油位 oil level gauge 油标,油位计 oil level indicator 油位指示器 oil pan 油盘 oil piping 油管 oil quench 油淬火 oil receiver 油盘 oil reservoir 油池 oil ring 油环 oil seal 油封 oil spray 油雾 oil sump gasket 油槽垫圈 oil tank 油箱 oil waste box 油渣盒 oil wick 油绳 oil wiper ring 挡油环 oilier 给油器 oil-immersed 浸油的 o