[1] : The Collaborative International Dictionary of English v.0.48

stopcock \stop"cock`\, n.
   1. a bib, faucet, or short pipe, fitted with a turning
      stopper or plug for permitting or restraining the flow of
      a liquid or gas; a cock or valve for checking or
      regulating the flow of water, gas, etc., through or from a
      pipe, etc.
      1913 webster

   2. the turning plug, stopper, or spigot of a faucet. r.
      1913 webster

[2] : WordNet (r) 2.0

stopcock
     n : faucet consisting of a rotating device for regulating flow
         of a liquid syn: cock, turncock
see also:
cock turncock 

Stopcock >> S Words
Stopcock, definition of term: Stopcock
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