truth serum
Noun
Meaning
truth serum (countable and uncountable, plural truth serums or truth sera)
(informal, medicine) A psychoactive medication, especially one administered by injection, which supposedly renders a person cooperative and disposed to respond honestly to questions.
Synonyms
Hyponyms
Examples
Separate tests of THC as a truth serum were equally unsuccessful.
She sends for Snape, demanding that he provide the magical truth serum Veritaserum in order to force Harry to reveal any information he may be hiding.