peridinium

noun

peri·​din·​i·​um

ˌperəˈdinēəm

1

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

2

plural peridiniums

-ēəmz

or peridinia

-ēə

: any flagellate of the genus Peridinium

Word History

Etymology

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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