class Chlorophyceae vs order Chlorococcales

class Chlorophyceae and order Chlorococcales both are nouns.

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

class Chlorophyceae (noun)	order Chlorococcales (noun)
algae distinguished chiefly by having flagella and a clear green color, their chlorophyll being masked little if at all by other pigments	unicellular green algae that reproduce by spores