plural noun
Peri·​di·​ni·​idae | \ ˌperədə̇ˈnīəˌdē\

Definition of Peridiniidae

: a family of marine and freshwater dinoflagellates that have a thick test composed of plates and well-marked flagellar grooves — compare ceratium , gonyaulax , peridiniaceae

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History and Etymology for Peridiniidae

borrowed from New Latin, from Peridinium peridinium + -idae -idae

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a strong desire or propensity

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