A medical instrument that records several physiological processes simultaneously (e.g., pulse rate and blood pressure and respiration and perspiration) WordNet 3.0 & Open English WordNet

A polygraph, often incorrectly referred to as a lie detector test, is a junk science device or procedure that measures and records several physiological indicators such as blood pressure, pulse, respiration, and skin conductivity while a person is asked and answers a series of questions. Wikipedia

Forensic instrument. Wikipedia Disambiguation

Device or procedure that attempts to infer lying by measuring physiological indicators Wikidata

A device which measures and records several physiological variables such as blood pressure, heart rate, respiration and skin conductivity while a series of questions is being asked to a subject, in an attempt to detect lies. Wiktionary