# clam up

> English word · Verb

## Definitions
1. To become silent; to stop talking.
2. To make or become clammy.

## Etymology
By analogy with a clam closing itself. Compare clamshell (“mouth”), clam (“mouth”).

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/clam-up