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lie detector

noun

Simple 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of lie detector

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

Examples of lie detector in a sentence

  1. The murder suspect failed a lie detector test.

  2. <hooked the suspect up to a lie detector before interrogating him about the robbery>



1909

First Known Use of lie detector

1909

Rhymes with lie detector


Medical Dictionary

lie detector

play
noun \ˈlī-di-ˌtek-tər\

Medical Definition of lie detector

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




Law Dictionary

lie detector

noun lie de·tec·tor

Legal Definition of lie detector

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




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