polygraph

noun
poly·​graph | \ ˈpä-lē-ˌgraf How to pronounce polygraph (audio) \

Definition of polygraph

: an instrument for recording variations of several different pulsations (as of physiological variables) simultaneously — compare lie detector

Other Words from polygraph

polygraphic \ ˌpä-​lē-​ˈgra-​fik How to pronounce polygraph (audio) \ adjective

Synonyms for polygraph

Synonyms

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With its graph- root, polygraph indicates that it writes out several different results. A polygraph's output consists of a set of squiggly lines on a computer screen, each indicating one function being tested. The functions most commonly measured are blood pressure, breathing rate, pulse, and perspiration, all of which tend to increase when you lie. Polygraphs have been in use since 1924, and have gotten more sensitive over the years, though many experts still believe that they're unreliable and that a prepared liar can fool the machine. They're used not only for law enforcement but perhaps more often by employers--often the police department itself!--who don't want to hire someone who has broken the law in the past but won't admit to it.

Examples of polygraph in a Sentence

They hooked him up to the polygraph and began the test. She was asked to take a polygraph.
Recent Examples on the Web Jemell Rayam was accused of stealing money and failed a polygraph test in 2009 — well before being promoted to the task force. Justin Fenton, baltimoresun.com, 13 Jan. 2022 When host Erie Outfitters of the Walleye Slam had a polygraph test given to Runyan and Comisky at a Toledo site, both passed. D'arcy Egan, cleveland, 23 Dec. 2021 Early in 1996, Hollander says, Steve persuaded her to meet him in Dallas and bring the videotape of her polygraph test. Thomas Lake, CNN, 8 Dec. 2021 After 16 months working for the US, Pardis was terminated in 2012 after failing a routine polygraph, or lie detector, test. Anna Coren, CNN, 22 July 2021 Several people, including Shonda’s friends, were questioned at the time and given polygraph tests in Capt. Andrea Cavallier, NBC News, 4 July 2021 The affidavit said Barry Morphew refused to take a polygraph in the days after his wife vanished. Fox News, 9 Nov. 2021 Based on Pavlinac's statements, and that Sosnovke failed a polygraph test, authorities arrested Sosnovke on murder charges. Joseph Diaz, ABC News, 4 Nov. 2021 Barry Morphew refused to take a polygraph test in the days after his wife was reported missing on May 10, 2020, which was Mother's Day, the affidavit said. CBS News, 21 Sep. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'polygraph.' 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 polygraph

1871, in the meaning defined above

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Time Traveler for polygraph

Time Traveler

The first known use of polygraph was in 1871

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Dictionary Entries Near polygraph

Polygordius

polygraph

polygrapher

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Statistics for polygraph

Last Updated

17 Jan 2022

Cite this Entry

“Polygraph.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/polygraph. Accessed 17 Jan. 2022.

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More Definitions for polygraph

polygraph

noun

English Language Learners Definition of polygraph

: a test that is done with a lie detector to see if someone is telling the truth

polygraph

noun
poly·​graph | \ ˈpäl-i-ˌgraf How to pronounce polygraph (audio) \

Medical Definition of polygraph

: an instrument for simultaneously recording variations of several different pulsations (as of the pulse, blood pressure, and respiration) — see lie detector

Other Words from polygraph

polygraphic \ ˌpäl-​i-​ˈgraf-​ik How to pronounce polygraph (audio) \ adjective
polygraphically \ -​i-​k(ə-​)lē How to pronounce polygraph (audio) \ adverb

polygraph

noun
poly·​graph | \ ˈpä-lē-ˌgraf How to pronounce polygraph (audio) \

Legal Definition of polygraph

: an instrument that records physiological pulsations especially : lie detector

Other Words from polygraph

polygraphic \ ˌpä-​lē-​ˈgra-​fik How to pronounce polygraph (audio) \ adjective

More from Merriam-Webster on polygraph

Britannica.com: Encyclopedia article about polygraph

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