class Phaeophyceae vs order Laminariales

class Phaeophyceae and order Laminariales both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Phaeophyceae	Yes	No	No	No
order Laminariales	Yes	No	No	No

class Phaeophyceae (noun)	order Laminariales (noun)
brown algae; mostly marine and littoral eukaryotic algae	in some classifications coextensive with family Laminariaceae: marine brown algae of cold or polar seas