environment vs sphere

environment and sphere both are nouns.

Word	Noun	Adjective	Verb	Adverb
environment	Yes	No	No	No
sphere	Yes	No	No	No

As nouns, sphere is a hyponym of environment; that is, sphere is a word with a more specific, narrower meaning than environment:

environment (noun)	sphere (noun)
the area in which something exists or lives	any spherically shaped artifact
the totality of surrounding conditions	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