urban area vs geographic region

urban area and geographic region both are nouns.

Word	Noun	Adjective	Verb	Adverb
urban area	Yes	No	No	No
geographic region	Yes	No	No	No

As nouns, geographic region is a hypernym of urban area; that is, geographic region is a word with a broader meaning than urban area:

Other hypernyms of urban area include geographic area, geographical area, geographical region.

urban area (noun)	geographic region (noun)
a geographical area constituting a city or town	a demarcated area of the Earth