loose lip

loose lip noun: the practice or characteristic of being overly talkative, especially with respect to inadvertently revealing information which is private or confidential.

Image: Public domain, via Wikimedia Commons

Noun

loose lip (plural loose lips)

(idiomatic, often pluralized) The practice or characteristic of being overly talkative, especially with respect to inadvertently revealing information which is private or confidential.
- Loose lips might sink ships.c. 1940, Slogan used by US government during World War II
- In the classic dramas of private investigation, the cheeky quip is the tough guy's challenge to toughness. In Fletch the quick, smartly paced gags somehow read as signs of vulnerability. . . . Every minute you expect the hero's loose lip to be turned into a fat one.1985 June 3, Richard Schickel, “Cinema: Gliberated in Dreamland Fletch”, in Time
Synonyms:

big mouth, loquaciousness

Synonyms of loose lip

Forms of loose lip

plural	loose lips

Words formed from loose lip

Questions about loose lip

What does loose lip mean?: Loose lip means the practice or characteristic of being overly talkative, especially with respect to inadvertently revealing information which is private or confidential.
What part of speech is loose lip?: Loose lip is a noun.
What is the plural of loose lip?: The plural of loose lip is loose lips.

Words near loose lip in the dictionary

Adapted from Wiktionary: loose lip (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated: 2026-09-02

Pronunciation audio from Wikimedia Commons, each file under its own free license: En-au-loose lip.ogg.

Cite this entry: “loose lip.” Word.ws, https://word.ws/loose_lip. Based on Wiktionary, CC BY-SA 4.0.