class Chlorophyceae vs order Volvocales

class Chlorophyceae and order Volvocales both are nouns.

Word	Noun	Adjective	Verb	Adverb
class Chlorophyceae	Yes	No	No	No
order Volvocales	Yes	No	No	No

class Chlorophyceae (noun)	order Volvocales (noun)
algae distinguished chiefly by having flagella and a clear green color, their chlorophyll being masked little if at all by other pigments	chiefly freshwater green algae; solitary or colonial