: 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

Word History


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

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Dictionary Entries Near Meridion

Cite this Entry

“Meridion.” Dictionary, Merriam-Webster, Accessed 27 Feb. 2024.

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