giant clam

American  

[jahy-uhnt klam] / ˈdʒaɪ ənt ˈklæm /

noun

1. any of several huge clams of the family Tridacnidae, inhabiting the shallow waters of coral reefs in the tropical Indo-Pacific, including Tridacna squamosa fluted giant clam, a relatively hardy but conservation dependent species that grows to about 16 inches (40 centimeters) across.

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Etymology

Origin of giant clam

First recorded in 1945–50

Example Sentences

China declared it a national nature reserve and has banned giant clam harvesting—tactics analysts say are designed to harden its territorial claim.

From The Wall Street Journal • May 15, 2026

I built the chapters around seashells that were iconic to us, but some of those are eating seashells, and those include the bay scallop, the giant clam and the queen conch.

From Salon • Aug. 8, 2021

A giant clam with neon filaments in its mouth, which closed comically when Kerry gave it a tug.

From The New Yorker • May 30, 2018

Then, after wandering past the giant clam and the embalmed squids, they found the Milstein Hall of Ocean Life.

From The New Yorker • May 8, 2017

Fred sank to the bottom and hid behind a giant clam.

From "Nim’s Island" by Wendy Orr