rhabdomancy

n. searching for underground water or mineral ores using a divining rod

Rhabdomancy is a type of divination by means of any rod, wand, staff, stick, arrow, or the like. Specifically it has been used to describe various methods of divination, such as (a) setting staffs on end and watching where they fall, to divine the direction one should travel, or to find answers to certain questions, (b) divination by arrows (which have wooden shafts) - otherwise known as belomancy and (c) using a Y-shaped tree branch to locate the presence of underground minerals, metals, ores or water sources - in other words dowsing.
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Noun
1. searching for underground water or minerals by using a dowsing rod
(synonym) dowse, dowsing
(hypernym) divination, foretelling, soothsaying, fortune telling

(n.)
Same as Rabdomancy.
  

Divination using a stick or rod, such as dowsing for water