The Collaborative International Dictionary of English v.0.48:

Sluice \Sluice\, n. [OF. escluse, F. ['e]cluse, LL. exclusa,
   sclusa, from L. excludere, exclusum, to shut out: cf. D.
   sluis sluice, from the Old French. See Exclude.]
   1. An artifical passage for water, fitted with a valve or
      gate, as in a mill stream, for stopping or regulating the
      flow; also, a water gate or flood gate.
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   2. Hence, an opening or channel through which anything flows;
      a source of supply.
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            Each sluice of affluent fortune opened soon.
                                                  --Harte.
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            This home familiarity . . . opens the sluices of
            sensibility.                          --I. Taylor.
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   3. The stream flowing through a flood gate.
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   4. (Mining) A long box or trough through which water flows,
      -- used for washing auriferous earth.
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   Sluice gate, the sliding gate of a sluice.
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