Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English


English definition of “polygraph”


noun [C]     /ˈpɒl.ɪ.ɡrɑːf/ US  /ˈpɑː.lɪ.ɡræf/
a piece of electronic equipment used to try to discover if someone is telling lies Relating to detection and solving crimesLies, lying and hypocrisyDishonest people → Synonym lie detector
(Definition of polygraph noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
Focus on the pronunciation of polygraph

Definitions of “polygraph” in other dictionaries

Translations of “polygraph”

Word of the Day


to mix eggs with a little milk and mix again as they are being fried

Word of the Day


Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More