Me·​rid·​i·​on | \ mə̇ˈridēˌän \

Definition of Meridion

: a genus (coextensive with the family Meridionaceae) of freshwater pennate diatoms having cuneate cells arranged in flat, fan-shaped, or spiral colonies and often causing odors in public water supplies

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History and Etymology for Meridion

New Latin, from Greek, diminutive of merid-, meris part, portion

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Cite this Entry

“Meridion.” Dictionary, Merriam-Webster, Accessed 16 Feb. 2020.

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