rural area vs geographic region

rural area and geographic region both are nouns.

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

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

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

rural area (noun)	geographic region (noun)
an area outside of cities and towns	a demarcated area of the Earth