valency vs biological science

valency and biological science both are nouns.

Word	Noun	Adjective	Verb	Adverb
valency	Yes	No	No	No
biological science	Yes	No	No	No

valency (noun)	biological science (noun)
(chemistry) a property of atoms or radicals; their combining power given in terms of the number of hydrogen atoms (or the equivalent)	the science that studies living organisms
(biology) a relative capacity to unite or react or interact as with antigens or a biological substrate
the phenomenon of forming chemical bonds