a hole or hollow area in which liquid waste collects 集水坑；污水池 - (North American English also oil pan)
the place under an engine that holds the engine oil （发动机下面的）集油槽，油底壳
Word OriginMiddle English (in the sense ‘marsh’): from Middle Dutch or Low German sump, or (in the mining sense) from German Sumpf; related to swamp.