noun ple·thys·mo·thal·lus \pləˌthizməˈthaləs, -ism-\

Definition of plethysmothallus

  1. :  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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Origin and Etymology of plethysmothallus

New Latin, from Greek plēthysmos multiplication + New Latin thallus

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a trip made at another's expense

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