Noun | 1. | class Phaeophyceae - brown algae; mostly marine and littoral eukaryotic algae division Phaeophyta, Phaeophyta - coextensive with class Phaeophyceae; in some classifications subsumed in the division Heterokontophyta brown algae - algae having the chlorophyll masked by brown and yellow pigments Laminariales, order Laminariales - in some classifications coextensive with family Laminariaceae: marine brown algae of cold or polar seas Fucales, order Fucales - coextensive with the family Fucaceae class - (biology) a taxonomic group containing one or more orders |