Osteostraci vs suborder Osteostraci

Osteostraci and suborder Osteostraci both are nouns.

Word	Noun	Adjective	Verb	Adverb
Osteostraci	Yes	No	No	No
suborder Osteostraci	Yes	No	No	No

As nouns, Osteostraci and suborder Osteostraci are synonyms defined as:

Osteostraci and suborder Osteostraci: extinct group of armored fish-like vertebrates; taxonomy is not clear

Other synonyms of Osteostraci include Cephalaspida, suborder Cephalaspida.

Osteostraci (noun)	suborder Osteostraci (noun)
extinct group of armored fish-like vertebrates; taxonomy is not clear	extinct group of armored fish-like vertebrates; taxonomy is not clear