From The Collaborative International Dictionary of English v.0.48:
Sump \Sump\, n. [Cf. G. sumpf a sump in a mine, a swamp, akin to
LG. sump, D. somp a swamp, Dan. & Sw. sump, and perhaps to E.
swamp.]
1. (Metal.) A round pit of stone, lined with clay, for
receiving the metal on its first fusion. --Ray.
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2. The cistern or reservoir made at the lowest point of a
mine, from which is pumped the water which accumulates
there.
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3. A pond of water for salt works. --Knight.
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4. A puddle or dirty pool. [Prov. Eng.]
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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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