home ground vs environment

home ground and environment both are nouns.

Word	Noun	Adjective	Verb	Adverb
home ground	Yes	No	No	No
environment	Yes	No	No	No

As nouns, environment is a hypernym of home ground; that is, environment is a word with a broader meaning than home ground:

home ground: the type of environment in which an organism or group normally lives or occurs
environment: the area in which something exists or lives

Other hypernyms of home ground include environs, surround, surroundings.

home ground (noun)	environment (noun)
the type of environment in which an organism or group normally lives or occurs	the area in which something exists or lives
	the totality of surrounding conditions