DOWSER

n. person who uses a divining rod to find water (or metal, etc.)

Dowsing, sometimes called divining or water witching, refers to practices which some people claim enables them to detect hidden water, metals, gemstones or other objects, usually obstructed by land or sometimes located on a map. Most commonly, the movement or vibrations of apparatus, such as a Y-shaped twig, an L-shaped rod or a pendulum, is used in the practice. Some practitioners use no apparatus at all.
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Noun
1. someone who uses a divining rod to find underground water
(synonym) water witch, rhabdomancer
(hypernym) diviner
(derivation) dowse
2. forked stick that is said to dip down to indicate underground water or oil
(synonym) divining rod, dowsing rod, waterfinder, water finder
(hypernym) stick
(derivation) dowse

(n.)
One who uses the dowser or divining rod.
  

(n.)
A divining rod used in searching for water, ore, etc., a dowsing rod.
  

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