Word Study
tridacna
CIDE DICTIONARY
tridacna, n. [L., pl., a kind of oysters, fr. Gr. eaten at three bites, tri- + to bite.].
A genus of very large marine bivalve shells found on the coral reefs of the Indian and Pacific Oceans. One species (Tridacna gigas ) often weighs four or five hundred pounds, and is sometimes used for baptismal fonts. Called also paw shell , and fountain shell . [1913 Webster]
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