: a large genus of red algae (family Rhodomelaceae) having usually a filamentous much-branched thallus variable in shape and size but in cross section showing a single axial cell surrounded by a sheath of tubular cells at least in the axis and main branches

Word History


New Latin, from poly- + siphon- + -ia

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Dictionary Entries Near Polysiphonia

Cite this Entry

“Polysiphonia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Polysiphonia. Accessed 21 Apr. 2024.

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