volleyball vs volleyball game

volleyball and volleyball game both are nouns.

Word	Noun	Adjective	Verb	Adverb
volleyball	Yes	No	No	No
volleyball game	Yes	No	No	No

As nouns, volleyball and volleyball game are synonyms defined as:

volleyball and volleyball game: a game in which two teams hit an inflated ball over a high net using their hands

Other synonyms of volleyball include volley ball.

volleyball (noun)	volleyball game (noun)
a game in which two teams hit an inflated ball over a high net using their hands	a game in which two teams hit an inflated ball over a high net using their hands
an inflated ball used in playing volleyball