plural noun
Mac·​tri·​dae | \ -rəˌdē\

Definition of Mactridae

: a widely distributed family of marine clams (suborder Tellinacea) that have closely fitting or slightly gapping shells with two cardinal teeth in each valve and fused ensheathed siphons of equal length and that comprise the surf clams — compare lutraria , mactra, spisula

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History and Etymology for Mactridae

New Latin, from Mactra, type genus + -idae

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