lie detector


: 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 The star of Russian Doll plays Charlie Cale, a human lie detector on the run from a shady casino enforcer (Benjamin Bratt). Brian Tallerico, Vulture, 18 Apr. 2024 Dan Hurley on lie detector The Huskies weren’t expected to have this much success – beating teams by an average of 27.8 points in the tournament – after their national championship last year, losing five of their top eight players. Joe Arruda, Hartford Courant, 5 Apr. 2024 Casey Anthony’s mom, Cindy, had to walk away from a lie detector test after suffering a panic attack while she was questioned about her late granddaughter, Caylee. Jager Weatherby, New York Daily News, 4 Jan. 2024 From vast biometric data collected without consent in refugee camps, to algorithms replacing visa officers and making discriminatory decisions, to AI lie detectors used at borders, the roll out of unregulated technologies is ever-growing. Petra Molnar, TIME, 21 May 2024 Enter Kohler, who commissioned a lie detector test that Sutton passed. Steve Henson, Los Angeles Times, 11 Apr. 2024 Before the performance and interview, the show began with the superstar undergoing a playful lie detector test. Isabela Raygoza, Billboard, 26 Mar. 2024 But things were far more complicated for contestants, who agreed to take a lie detector test and answer a series of increasingly personal questions., 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

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.” Dictionary, Merriam-Webster, Accessed 21 Jun. 2024.

Kids Definition

lie detector

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

Medical Definition

lie detector

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

Legal Definition

lie detector

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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