semidesert vs geographical area

semidesert and geographical area both are nouns.

Word	Noun	Adjective	Verb	Adverb
semidesert	Yes	No	No	No
geographical area	Yes	No	No	No

As nouns, geographical area is a hypernym of semidesert; that is, geographical area is a word with a broader meaning than semidesert:

semidesert: a region much like a desert but usually located between a desert and the surrounding regions
geographical area: a demarcated area of the Earth

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

semidesert (noun)	geographical area (noun)
a region much like a desert but usually located between a desert and the surrounding regions	a demarcated area of the Earth