What does "sump" mean?

Sump: The cistern or reservoir made at the lowest point of a mine, from which is pumped the water which accumulates there.

Additional senses

  1. 2.A pond of water for salt works. Knight.
  2. 3.A puddle or dirty pool. [Prov. Eng.] Sump fuse, a fuse used in blasting under water. -- Sump men (Mining), the men who sink the sump in a mine.

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