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 But things were far more complicated for contestants, who agreed to take a lie detector test and answer a series of increasingly personal questions. EW.com, 15 Feb. 2024 In a new special on A&E, both of Casey's parents — mother Cindy and father George — take lie detector tests on camera and reflect on the death of their granddaughter Caylee. Brenton Blanchet, Peoplemag, 4 Jan. 2024 Cindy and George took lie detector tests in a documentary telling their side of the story Cindy and George sat down to take a filmed lie detector test airing in January 2024. Rebecca Aizin, Peoplemag, 5 Jan. 2024 Radcliffe revealed some secrets while taking part in a lie detector test for 'Vanity Fair' Daniel Radcliffe is revealing some secrets! Gabrielle Rockson, Peoplemag, 18 Oct. 2023 The trailer starts off showing Bomer’s character Hawkins Fuller, who works behind the scenes in politics, being interrogated by government officials and taking a lie detector test about his personal life and affiliations. Kimberlee Speakman, Peoplemag, 3 Oct. 2023 The quip came when the Modern Family actress was tasked with taking a lie detector test on stage at Cowell's request. Kelly Martinez, Peoplemag, 27 Sep. 2023 Natalia Dyer shares her first impression of Charlie Heaton Dyer and Charlie sat down to ask each other a series of questions for Vanity Fair's lie detector test series, which included Dyer spilling her first impressions of the actor. Jacqueline Weiss, Peoplemag, 26 Apr. 2023 From comparing his acting skills to that of Lady Gaga and Cher to trolling Kelly Clarkson, Troye Sivan got a lot of things off his chest during his lie detector test with Vanity Fair on Wednesday (Aug. 16). Kyle Denis, Billboard, 17 Aug. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'lie detector.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1909, in the meaning defined above

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

Dictionary Entries Near lie detector

Cite this Entry

“Lie detector.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lie%20detector. Accessed 19 Mar. 2024.

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

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