acanthopterygian vs spiny-finned fish

acanthopterygian and spiny-finned fish both are nouns.

Word	Noun	Adjective	Verb	Adverb
acanthopterygian	Yes	No	No	No
spiny-finned fish	Yes	No	No	No

As nouns, acanthopterygian and spiny-finned fish are synonyms defined as:

acanthopterygian and spiny-finned fish: a teleost fish with fins that are supported by sharp inflexible rays

acanthopterygian (noun)	spiny-finned fish (noun)
a teleost fish with fins that are supported by sharp inflexible rays	a teleost fish with fins that are supported by sharp inflexible rays