truth serum

American  

[trooth seer-uhm] / ˈtruθ ˌsɪər əm /

Often truth drug

noun

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.

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Etymology

Origin of truth serum

First recorded in 1920–25

Example Sentences

As the YouTube hit demonstrates, hot sauce isn’t just for daredevils and masochists: It’s a truth serum.

From The Wall Street Journal • Nov. 20, 2025

The playfulness kicks in when George and Kathryn invite the other suspects over for a dinner spiced with garlic and truth serum.

From Los Angeles Times • Mar. 13, 2025

“If opening day was today, he would certainly be running out there in center, which I know he loves. I think if you put truth serum in him, that’s what he’d want to do, regardless.”

From Seattle Times • Dec. 7, 2023

But you know, if you really have me under truth serum and say, you know, how confident am I?

From New York Times • Dec. 10, 2021

“The truth serum has revealed that while you may be a fool, you are no traitor. This interrogation is over. You may leave.”

From "Allegiant" by Veronica Roth