Home › Words › P › phaeophyceanphaeophyceanphaeophycean · noun — any member of the Phaeophyceae; a brown alga.Definition from Wiktionary (CC BY-SA 3.0).EtymologyPhaeophyceae + -announAny member of the Phaeophyceae; a brown alga.Definitions & examples from Wiktionary (CC BY-SA 3.0).