clam¹ (klăm)
n.

1. 1. Any of various usually burrowing marine and freshwater bivalve mollusks of the class Pelecypoda, including members of the genera Venus and Mya, many of which are edible.
   2. The soft edible body of such a mollusk.
2. Informal. A close-mouthed person, especially one who can keep a secret.
3. Slang. A dollar: set me back 75 clams.

intr.v., clammed, clam·ming, clams.
To hunt for clams.

phrasal verb:

clam up Informal.

1. To refuse to talk.

[From obsolete clam-shell, shell that clamps, clam, from CLAM².]

clammer clam'mer n.

clam² (klăm)
n.
A clamp or vise.

[Middle English, from Old English clam, clamm, bond, fetter.]

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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

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