plethysmothallus

noun

ple·​thys·​mo·​thal·​lus

pləˌthizməˈthaləs,

-ism-

: 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

Word History

Etymology

New Latin, from Greek plēthysmos multiplication + New Latin thallus

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