umpire vs referee

umpire and referee both are nouns.

Word	Noun	Adjective	Verb	Adverb
umpire	Yes	No	Yes	No
referee	Yes	No	Yes	No

As verbs, umpire and referee are synonyms defined as:

umpire (noun)	referee (noun)
an official at a baseball game	(sports) the chief official (as in boxing or American football) who is expected to ensure fair play
someone chosen to judge and decide a disputed issue	someone who reads manuscripts and judges their suitability for publication
	an attorney appointed by a court to investigate and report on a case

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