a polygraph used to determine changes in certain body activities, as blood pressure, pulse, breathing, and perspiration, the results of which may be interpreted to indicate the truth or falsity of a person's answers under questioning.
Origin of lie detector
An Americanism dating back to 1905–10
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for lie detector
Historical Examples of lie detector
He examined the indicators of the lie-detector with great care.
The Ruler flashed a look at the technicians handling the lie-detector.
It was obviously a form of lie-detector—and Korvin felt himself marveling again at this race.
They needed no words; the lie-detector was telling them, perfectly obviously, that he was speaking the truth.
Korvin's guards were standing around doing nothing of importance now that their captor was strapped down in the lie-detector.
British Dictionary definitions for lie detector
a polygraph used esp by a police interrogator to detect false or devious answers to questions, a sudden change in one or more involuntary physiological responses being considered a manifestation of guilt, fear, etcSee polygraph (def. 1), galvanic skin response
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
A polygraph used to detect possible deception during an interrogation.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.