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

penstock \pen"stock\, n. etymol. uncertain; perh. fr. pen an
   inclosure + stock.
   1. a close conduit or pipe for conducting water, as, to a
      water wheel, or for emptying a pond, or for domestic uses.
      1913 webster

   2. the barrel of a wooden pump.
      1913 webster

[2] : WordNet (r) 2.0

penstock
     n 1: regulator consisting of a valve or gate that controls the
          rate of water flow through a sluice syn: sluicegate,
          sluice valve, floodgate, head gate, water gate
     2: conduit that carries a rapid flow of water controlled by a
        sluicegate syn: sluice, sluiceway
see also:
sluicegate sluice valve floodgate head gate water gate sluice 
sluiceway 

[3] : Moby Thesaurus II by Grady Ward, 1.0

21 moby thesaurus words for "penstock":
   aboideau, air lock, chute, dock gate, eaves trough, flood-hatch,
   floodgate, gate, guide, gutter, head gate, lock, lock gate,
   pentrough, shoot, sluice, sluice gate, tide gate, trough,
   water gate, weir

Penstock >> P Words
Penstock, definition of term: Penstock
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