sump

中文： 集水坑、油底壳

1. A hollow or pit into which liquid drains, such as a cesspool, cesspit or sink.
2. The lowest part of a mineshaft into which water drains.
3. A completely flooded cave passage, sometimes passable by diving.
4. The crankcase or oil reservoir of an internal combustion engine.
5. The pit at the lowest point in a circulating or drainage system (FM 55-501).
6. An intentional depression around a drain or scupper that promotes drainage.

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