official vs ex officio

official is a noun but ex officio is not a noun.

Word	Noun	Adjective	Verb	Adverb
official	Yes	Yes	No	No
ex officio	No	Yes	No	Yes

official (noun)	ex officio (noun)
someone who administers the rules of a game or sport
a worker who holds or is invested with an office

official (adjective)	ex officio (adjective)
having official authority or sanction	by virtue of an office or position
of or relating to an office
verified officially
(of a church) given official status as a national or state institution
conforming to set usage, procedure, or discipline

official (adverb)	ex officio (adverb)
	by virtue of position