clam up

VERB
7 LETTERS · STARTS WITH C

clam up is a valid 7-letter word worth 12 points in Scrabble and 17 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
C3L1A1M3U1P3
3 + 1 + 1 + 3 + 0 + 1 + 3 =12 PTS
DOUBLE WORD → 24TRIPLE WORD → 36
MEANING

What does clam up mean?

VERB · 1 SENSE
1

Refuse to talk or stop talking; fall silent.