dowser

from WordNet (r) 3.0 (2006)

dowser
    n 1: someone who uses a divining rod to find underground water
         [syn: {water witch}, {dowser}, {rhabdomancer}]
    2: forked stick that is said to dip down to indicate underground
       water or oil [syn: {divining rod}, {dowser}, {dowsing rod},
       {waterfinder}, {water finder}]

from The Collaborative International Dictionary of English v.0.48

Dowser \Dows"er\, n.
   1. A divining rod used in searching for water, ore, etc., a
      dowsing rod. [Colloq.]
      [1913 Webster]

   2. One who uses the dowser or divining rod. --Eng. Cyc.
      [1913 Webster]

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