form family vs biological science

form family and biological science both are nouns.

Word	Noun	Adjective	Verb	Adverb
form family	Yes	No	No	No
biological science	Yes	No	No	No

form family (noun)	biological science (noun)
(biology) an artificial taxonomic category for organisms of which the true relationships are obscure; ranked between order and genus	the science that studies living organisms