central processing unit vs mainframe

central processing unit and mainframe both are nouns.

Word	Noun	Adjective	Verb	Adverb
central processing unit	Yes	No	No	No
mainframe	Yes	No	No	No

As nouns, central processing unit and mainframe are synonyms defined as:

central processing unit and mainframe: (computer science) the part of a computer (a microprocessor chip) that does most of the data processing

Other synonyms of central processing unit include C.P.U., central processor, CPU, processor.

central processing unit (noun)	mainframe (noun)
(computer science) the part of a computer (a microprocessor chip) that does most of the data processing	(computer science) the part of a computer (a microprocessor chip) that does most of the data processing
	a large digital computer serving 100-400 users and occupying a special air-conditioned room