noun tri·dac·na \trə̇ˈdaknə\

Definition of tridacna

  1. 1 capitalized :  a genus of marine bivalves (family Tridacnidae) having no anterior adductor muscle and an equivalve shell the valves of which are very thick and heavy and strongly plicated at the margin — see giant clam

  2. 2 plural -s :  any mollusk of the genus Tridacna :  giant clam

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Origin and Etymology of tridacna

New Latin, from Latin, an oyster, from Greek tridaknos eaten at three bites, from tri- three + -daknos (from daknein to bite) — more at tongs

Seen and Heard

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to cast off or become cast off

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