clam up
verbEtymology By analogy with a clam closing itself. Compare clamshell (“mouth”), clam (“mouth”).
1
Informal To become silent; to stop talking.
- Maybe he … or she … was a witness who refused to clam up … a whistle blower …1986, Paul Chadwick, Concrete: Under the Desert Stars, Dark Horse Books:
- Teenagers' father. Alright, Matt, I think you've made your point. Matt Foley: Dad, I sincerely wish you'd do everyone a great service, and clam up!1993, “Matt Foley: A Scary Story on Halloween”, in Saturday Night Live, season 19, spoken by Matt Foley (Chris Farley):
1 more example
- “You can't clam up on me, punk! I know you're hiding something!” “Okay! Okay! I'm the one taking dumps in the urinals! I call it an "inside the park home run"! (sobbing)” “Smith, good work. Dick, that's a funny name for it.”2016 June 13, Charles Suozzi, “Gift Me Liberty” (6:11 from the start), in American Dad!, season 13, episode 20, spoken by Stan Smith (Seth MacFarlane):
2
Ambitransitive To make or become clammy.
- Antonyms
- talk