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Mactra

noun Mac·tra \ ˈmaktrə \
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Definition of Mactra

: the type genus of Mactridae formerly including most members of the family but now restricted to a few somewhat triangular, usually thin-shelled surf clams
—

mactroid

\-ˌtrȯid\ adjective

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Origin and Etymology of mactra

New Latin, from Greek maktra kneading trough, from massein to knead

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