Oxford vs Oxonian

Oxford and Oxonian both are nouns.

Word	Noun	Adjective	Verb	Adverb
Oxford	Yes	No	No	No
Oxonian	Yes	Yes	No	No

Oxford (noun)	Oxonian (noun)
a university in Oxford, England	a native or resident of Oxford
a city in southern England to the northwest of London; site of Oxford University
a university town in northern Mississippi; home of William Faulkner

Oxford (adjective)	Oxonian (adjective)
	of or pertaining to or characteristic of the city of Oxford, England, or its inhabitants
	of or pertaining to or characteristic of Oxford University