• synonyms


  1. a genus of giant clams inhabiting reefs in the South Pacific, attaining a diameter of 4 feet (1.2 meters) or more, and weighing over 500 pounds (227 kg).
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Origin of Tridacna

1770–80; < New Latin, noun use of feminine of Latin tridacnus requiring three bites < Greek trídaknos, equivalent to tri- tri- + dákn(ein) to bite + -os adj. suffix
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for tridacna

Historical Examples

  • Tridacna is distinguished from Hippopus by the large opening in the hinge.

    A Conchological Manual

    George Brettingham Sowerby

  • A tridacna spread its jaws before his steps so that he nearly plunged into the deadly springtrap of the deep.

  • The former is supposed to have originated from the tridacna shell, the latter from the taro.

  • The shell of the Tridacna gigas is the largest anywhere known.

  • The valves of Tridacna gigas are sometimes found a yard and a half in length, and weighing five hundred pounds.

    The Ocean World:

    Louis Figuier