referee vs peer review

referee is a noun but peer review is not a noun.

Word	Noun	Adjective	Verb	Adverb
referee	Yes	No	Yes	No
peer review	No	No	Yes	No

As verbs, referee and peer review are synonyms defined as:

referee (noun)	peer review (noun)
(sports) the chief official (as in boxing or American football) who is expected to ensure fair play
someone who reads manuscripts and judges their suitability for publication
an attorney appointed by a court to investigate and report on a case

referee (verb)	peer review (verb)
evaluate professionally a colleague's work	evaluate professionally a colleague's work
be a referee or umpire in a sports competition