clam up
verb
clammed up; clamming up; clams up
intransitive verb
: to become silent
clammed up and refused to talk
Synonyms
- belt up [British]
- dry up
- dummy up
- hush
- pipe down
- quiet (down)
- shut up
See all Synonyms & Antonyms 
Example Sentences
the little girl clammed up when the doctor came into the room
Word History
First Known Use
1916, in the meaning defined above
clams up
verb
as in dries up
to stop talking the little girl clammed up when the doctor came into the room Synonyms & Similar Words
Relevance
- dries up
- hushes
- shuts up
- belts up
- dummies up
- holds one's peace
- pipes down
- quiets (down)
- holds one's tongue
- calms (down)
- settles (down)
- cools (down)
- haws
- hems
Antonyms & Near Antonyms
- speaks
- talks
- speaks out
- talks up
- spouts (off)
- speaks up
- pipes up
- sounds off