dowser
/ˈdaʊsər/Definitions
1. noun
a person who uses a divining rod or other device to locate underground water, minerals, or other substances
“The prospector used a dowsing rod to search for oil in the area.”
2. verb
to locate or detect something, especially a substance such as water or minerals, by using a dowsing rod or other device
“The geologist was said to dowse for hidden underground streams.”