Cite
 

Meaning of truth serum

truth' se"rum

Pronunciation: [key]
  1. a drug, as the barbiturate thiopental, that induces in the subject a desire to talk or a state of heightened suggestibility, used in psychotherapy and in interrogation to discover repressed or consciously withheld information.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.