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tridacna

noun tri·dac·na \ trə̇ˈdaknə \

Definition of tridacna

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 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)

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