noun
polygraph
PO-leeg-raf
noun
1
A device, popularly called a lie detector, that records changes in breathing, pulse, and skin response while someone answers questions.
"The suspect agreed to take a polygraph test to clear his name."
How to Use Polygraph
Learner’s notesIn plain EnglishA machine that measures physical signs like heart rate to try to tell if someone is lying.
Common pairings
polygraph test
pass a polygraph
fail a polygraph
Word Forms
polygraphed past tense, polygraphs plural, polygraphs singular
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The suspect agreed to take a _____ test to clear his name.
Etymology
From poly- ("many") and -graph ("writing" or "recording"), originally referring to a device that recorded several measurements at once.