concatenate vs computer science

concatenate is not a noun while computer science is a noun.

Word	Noun	Adjective	Verb	Adverb
concatenate	No	No	Yes	No
computer science	Yes	No	No	No

concatenate (noun)	computer science (noun)
	the branch of engineering science that studies (with the aid of computers) computable processes and structures

concatenate (verb)	computer science (verb)
add by linking or joining so as to form a chain or series
combine two strings to form a single one