sphere vs geographical region

sphere and geographical region both are nouns.

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

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

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

sphere (noun)	geographical region (noun)
any spherically shaped artifact	a demarcated area of the Earth
a particular aspect of life or activity
the geographical area in which one nation is very influential
the apparent surface of the imaginary sphere on which celestial bodies appear to be projected
a solid figure bounded by a spherical surface (including the space it encloses)
a three-dimensional closed surface such that every point on the surface is equidistant from the center
a particular environment or walk of life