ˈpɑːliˌgræf 
British ˈpɒliˌgrɑːf
plural polygraphs
1
: lie detector
They hooked him up to the polygraph and began the test.
2
US
: a test that is done with a lie detector to see if someone is telling the truth
She was asked to take a polygraph.
Cite this Entry
“Polygraph.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/polygraph. Accessed 23 Jun. 2026.
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