C.P.U. vs computer science

C.P.U. and computer science both are nouns.

Word	Noun	Adjective	Verb	Adverb
C.P.U.	Yes	No	No	No
computer science	Yes	No	No	No

C.P.U. (noun)	computer science (noun)
(computer science) the part of a computer (a microprocessor chip) that does most of the data processing	the branch of engineering science that studies (with the aid of computers) computable processes and structures