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
clam up
verb
as in to dry up
to stop talking the little girl clammed up when the doctor came into the room Synonyms & Similar Words
Relevance
- dry up
- hush
- shut up
- dummy up
- pipe down
- hold one's peace
- quiet (down)
- belt up
- hold one's tongue
- calm (down)
- settle (down)
- cool (down)
- haw
- hem
Antonyms & Near Antonyms
- speak
- talk
- talk up
- speak out
- speak up
- spout (off)
- pipe up
- sound off