capitalized : the type genus of Peridiniidae comprising marine and freshwater dinoflagellates that are typically subspherical to ovoid in outline and that sometimes have the test prolonged into short horns compare ceratium
plural peridiniums
or peridinia
: any flagellate of the genus Peridinium

Word History


borrowed from New Latin, borrowed from Greek peridīn-, base of peridīneîn "to whirl, spin around" (from peri- peri- + dīneîn "to whirl, spin about") + New Latin -ium -ium

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Cite this Entry

“Peridinium.” Dictionary, Merriam-Webster, Accessed 3 Oct. 2023.

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