ple·​thys·​mo·​thal·​lus | \ pləˌthizməˈthaləs, -ism- \

Definition of plethysmothallus

: a dwarf filamentous thallus occurring in the life cycle of various brown algae and bearing at what appears to be a juvenile stage either unilocular or plurilocular sporangia

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History and Etymology for plethysmothallus

New Latin, from Greek plēthysmos multiplication + New Latin thallus

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Cite this Entry

“Plethysmothallus.” Dictionary, Merriam-Webster, Accessed 11 Jul. 2020.

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