polygraph: meaning, definition, pronunciation and examples
C1Formal, Technical, Legal
Quick answer
What does “polygraph” mean?
A machine designed to detect and record physiological signs (such as pulse rate, blood pressure, and perspiration) that are believed to indicate whether someone is telling the truth.
Audio
Pronunciation
Definition
Meaning and Definition
A machine designed to detect and record physiological signs (such as pulse rate, blood pressure, and perspiration) that are believed to indicate whether someone is telling the truth.
1. A device that records multiple physiological signals simultaneously; a medical or scientific instrument. 2. In a historical or literary context, an author who writes in multiple genres or on many subjects. This latter meaning is archaic.
Dialectal Variation
British vs American Usage
Differences
Meaning is identical. The American context is more prevalent due to the greater commonality of polygraph testing in law enforcement and some private sector pre-employment screening in the US. In the UK, its use is more restricted, typically to high-level security vetting or serious police investigations.
Connotations
Both varieties carry connotations of interrogation, scrutiny, and attempts to establish objective truth. In popular culture, it is strongly associated with crime dramas and espionage.
Frequency
The word is significantly more frequent in American English, reflecting its wider legal and employment usage.
Grammar
How to Use “polygraph” in a Sentence
[verb] + polygraph (e.g., take, administer, fail)polygraph + [noun] (e.g., test, results, examiner)Vocabulary
Collocations
Examples
Examples of “polygraph” in a Sentence
noun
British English
- The suspect was asked to undergo a polygraph as part of the vetting process.
- The scientist used a polygraph to monitor the patient's autonomic responses.
American English
- He had to take a polygraph for his clearance at the FBI.
- The defense attorney challenged the validity of the polygraph results.
Usage
Meaning in Context
Business
Rare, except in specific security-sensitive industries (e.g., defense contracting) for employee vetting. 'The candidate's offer is contingent on passing a polygraph.'
Academic
Used in forensic psychology, criminology, and law journals. 'The admissibility of polygraph evidence remains a contentious issue in common law jurisdictions.'
Everyday
Rare. Usually in the context of crime news or television shows. 'They hooked him up to a polygraph to see if he was lying.'
Technical
Standard term in forensic science and investigative procedures. 'The galvanic skin response component of the polygraph showed significant arousal.'
Vocabulary
Synonyms of “polygraph”
Neutral
Weak
Watch out
Common Mistakes When Using “polygraph”
- Using 'polygraph' to mean a general truth-telling session (e.g., 'Let's have a polygraph' instead of 'Let's be honest').
- Pronouncing it as /poʊˈlaɪ.ɡræf/ (like 'polite' with 'graph').
- Confusing it with 'polyglot' (a speaker of many languages).
FAQ
Frequently Asked Questions
No, polygraph tests are not considered 100% accurate by the scientific community. They measure stress and physiological arousal, which can be caused by factors other than lying, such as anxiety, fear, or physical discomfort. Their results are often inadmissible as evidence in many courts.
It is a subject of debate. Some claim countermeasures like controlled breathing or mental techniques can affect results, but polygraph examiners are trained to look for such attempts. The effectiveness of countermeasures is not reliably proven.
A standard polygraph typically measures and records several physiological indices: heart rate/blood pressure, respiration rate, and galvanic skin response (sweatiness of the palms), all of which are part of the autonomic nervous system.
No, 'polygraph' is primarily a noun. The action is described with verbs like 'administer a polygraph,' 'take a polygraph,' or 'be polygraphed.' The related professional is a 'polygraph examiner.'
A machine designed to detect and record physiological signs (such as pulse rate, blood pressure, and perspiration) that are believed to indicate whether someone is telling the truth.
Polygraph is usually formal, technical, legal in register.
Polygraph: in British English it is pronounced /ˈpɒl.ɪ.ɡrɑːf/, and in American English it is pronounced /ˈpɑː.li.ˌɡræf/. Tap the audio buttons above to hear it.
Phrases
Idioms & Phrases
- “(as) reliable as a polygraph (often used ironically to suggest unreliability)”
- “to be on the polygraph (meaning to be subjected to intense scrutiny)”
Learning
Memory Aids
Mnemonic
Think: POLY (many) + GRAPH (writing). The machine writes (graphs) many (poly) physiological signals.
Conceptual Metaphor
A TRUTH MACHINE / A LIE DETECTOR (The machine is personified as an objective arbiter of truth).
Practice
Quiz
In which professional field is the term 'polygraph' MOST specifically and commonly used?