geographical region vs Transcaucasia

geographical region and Transcaucasia both are nouns.

Word	Noun	Adjective	Verb	Adverb
geographical region	Yes	No	No	No
Transcaucasia	Yes	No	No	No

geographical region (noun)	Transcaucasia (noun)
a demarcated area of the Earth	a geographical region to the south of the Caucasus Mountains and to the north of Turkey that comprises Georgia and Armenia and Azerbaijan