tetherball vs athletic game

tetherball and athletic game both are nouns.

Word	Noun	Adjective	Verb	Adverb
tetherball	Yes	No	No	No
athletic game	Yes	No	No	No

As nouns, athletic game is a hypernym of tetherball; that is, athletic game is a word with a broader meaning than tetherball:

tetherball: a game with two players who use rackets to strike a ball that is tethered to the top of a pole; the object is to wrap the string around the pole
athletic game: a game involving athletic activity

tetherball (noun)	athletic game (noun)
a game with two players who use rackets to strike a ball that is tethered to the top of a pole; the object is to wrap the string around the pole	a game involving athletic activity