polygraph

poly- +‎ -graph

• Rhymes: -ɑːf

polygraph (plural polygraphs)

chart recorder often used with a
polygraph

1. 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.
2. (dated) A mechanical instrument for multiplying copies of a writing, resembling multiple pantographs.
3. (archaic) A collection of different works, either by one or several authors.
4. (linguistics) A group of letters that represent a single phoneme

• (device recording physiological measurements): lie detector
• (dated instrument for copying): manifold writer, autopen

Thomas Jefferson's polygraph copying device

• polygraph on Wikipedia.Wikipedia
• truth serum
• digraph, trigraph etc

polygraph (third-person singular simple present polygraphs, present participle polygraphing, simple past and past participle polygraphed)

1. (transitive) To administer a polygraph test to.

   The FBI polygraphed the suspect but learned nothing because they already knew he was lying.