Sphaerium

noun

Sphae·​ri·​um

ˈsfirēəm

: a widely distributed genus (the type of the family Sphaeriidae) of small viviparous freshwater bivalve mollusks that have a thin light-colored shell and the siphons separate see fingernail clam

Word History

Etymology

New Latin, from Greek sphairion, diminutive of sphaira ball, sphere

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