lie detector


Definition of lie detector

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

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Synonyms for lie detector


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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 Tonight also features the results of lie detector tests, and the results are sure to stir up the house. Katey Clifford, al, "How to watch the season finale of ‘Marriage Boot Camp: Hip Hop Edition’ | Live stream, TV channel, time," 3 Sep. 2020 Less innocuous activities include spy craft lessons with explosions and lie detector tests. Shaena Montanari, The Arizona Republic, "'My Spy' is a predictable addition to the spy comedy genre. But Dave Bautista makes it fun," 25 June 2020 Monday night, the attorney for the man who took the video of Abery's shooting told a news conference his client has taken a lie detector test, reports CBS Jacksonville affiliate WJAX-TV. CBS News, "Video shows officer trying to tase Ahmaud Arbery in 2017," 19 May 2020 Although King failed a lie detector test, this was not discussed at trial. Dallas Morning News, "Texas courts allow hypnosis despite science, overturned convictions," 9 Apr. 2020 So far courts have rejected fMRI lie detectors as evidence. Theodor Schaarschmidt, Scientific American, "The Art of Lying," 11 July 2018 From today’s perspective, this reasoning seems a bit overdramatic; even the latest lie detectors do not have that ability. Theodor Schaarschmidt, Scientific American, "The Art of Lying," 11 July 2018 Simmons has unequivocally denied any wrong doing and admitted to passing nine lie detector tests. Cori Murray, Essence, "Oprah Winfrey Cites Creative Differences Over Sexual Assault Documentary Set To Premiere At Sundance," 11 Jan. 2020 The men took out a black box that Dzhabrailov presumed was a lie detector but that turned out to be a machine that delivered electric shocks. Katy Steinmetz, Time, "A Victim of the Anti-Gay Purge in Chechnya Speaks Out: 'The Truth Exists'," 26 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lie detector.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of lie detector

1909, in the meaning defined above

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Time Traveler for lie detector

Time Traveler

The first known use of lie detector was in 1909

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Cite this Entry

“Lie detector.” Dictionary, Merriam-Webster, Accessed 29 Nov. 2020.

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More Definitions for lie detector

lie detector


English Language Learners Definition of lie detector

: a device used to measure the heart rate, breathing, etc., in order to find out if someone (such as a person suspected of a crime) is being honest

lie detector

\ ˈlī-di-ˌtek-tər How to pronounce lie detector (audio) \

Medical Definition of lie detector

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

lie detector

lie de·​tec·​tor

Legal Definition of lie detector

: an instrument for detecting physiological evidence of the tension that accompanies lying — compare polygraph

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