What does clammed mean?
"Clammed" is the informal past tense and past participle of the phrasal verb "clam up," meaning to fall suddenly and stubbornly silent. When a person clammed up, they stopped speaking altogether — often because they were nervous, embarrassed, defensive, or determined to keep a secret. The expression evokes the image of a clam snapping its shell tightly closed: nothing gets in, and nothing gets out. The word belongs firmly to casual, conversational English; it would sound odd in formal prose, where writers prefer "fell silent" or "refused to comment." It almost always occurs in the fixed phrase "clammed up," and it pairs naturally with contexts like interviews, interrogations, awkward conversations, and children hiding mischief. Its opposite is opening up or speaking freely. Though modest in register, the word is vivid and widely understood across British and American English, making it a useful shorthand for that familiar moment when someone shuts down mid-conversation and simply stops talking.
verbPast tense and past participle of the informal phrasal verb 'clam up,' meaning to suddenly stop talking or refuse to say anything, typically because one is nervous, embarrassed, or unwilling to share information.
- (of a person) stopped talking abruptly or refused to speak, usually from nervousness or secrecy — the informal past tense of 'clam up.'
"When the reporter asked about the missing funds, the treasurer simply clammed up."
"Under cross-examination, the suspect clammed up and answered no further questions."
"She used to chat freely at meetings, but after last month's criticism she clammed up completely."
When someone 'clams up,' English literally borrows the image of a clam snapping its shell shut — silence as an impenetrable shell you can't pry open.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of clammed
The word traces back to the noun "clam," which in Middle English originally meant a vice, clamp, or fastening device (from Old English "clamm," meaning bond or fetter), before shifting by the sixteenth century to mean the bivalve shellfish. The figurative verb "to clam up," drawing on the image of a clam closing its shell, arose as American colloquial English in the early twentieth century, with "clammed" as its natural past form. Related forms sharing the old sense of gripping or binding include "clamp" and "clasp."
Related word forms
How clammed is actually used
Strictly informal and conversational; out of place in formal writing. Almost always appears in the fixed phrase 'clammed up' rather than standing alone. Common in both British and American speech.
Easily confused with clammed
'Claimed' means asserted or demanded as one's own, whereas 'clammed' is the informal past tense of shutting up or going silent.