lie detector

noun

: a polygraph for detecting physiological evidence (such as change in heart rate) of the tension that accompanies lying

Examples of lie detector in a Sentence

The murder suspect failed a lie detector test. hooked the suspect up to a lie detector before interrogating him about the robbery
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Capricorn also testified that she was allegedly forced to take a five-day lie detector test after a bag of jewelry went missing. Tracy Wright, FOXNews.com, 28 May 2025 Capricorn Clark, who worked for Combs in two stints from 2004 to 2018, told a Manhattan jury that she was made to take lie detector tests over five days after three pieces of Combs' jewelry went missing. Janelle Griffith, People.com, 27 May 2025 George Kaplan, another former assistant who worked for Combs, testified last week that he was also ordered to take a lie detector test on two different occasions during his employment. Nbc News, NBC news, 27 May 2025 Clark also testified that she was subjected to a lie detector test after Combs accused her of stealing jewelry. Jenna Sundel joshua Rhett Miller, MSNBC Newsweek, 27 May 2025 See All Example Sentences for lie detector

Word History

First Known Use

1909, in the meaning defined above

Time Traveler
The first known use of lie detector was in 1909

Browse Nearby Words

Cite this Entry

“Lie detector.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lie%20detector. Accessed 9 Jun. 2025.

Kids Definition

lie detector

noun
: an instrument for detecting bodily changes (as an increase in heart rate) that are considered to go along with lying

Medical Definition

lie detector

noun
: a polygraph for detecting physiological evidence (as change in heart rate) of the tension that accompanies lying

Legal Definition

lie detector

noun
lie de·​tec·​tor
: an instrument for detecting physiological evidence of the tension that accompanies lying compare polygraph

More from Merriam-Webster on lie detector

Last Updated: - Updated example sentences
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