Special Olympics vs athletics

Special Olympics and athletics both are nouns.

Word	Noun	Adjective	Verb	Adverb
Special Olympics	Yes	No	No	No
athletics	Yes	No	No	No

As nouns, athletics is a hypernym of Special Olympics; that is, athletics is a word with a broader meaning than Special Olympics:

Special Olympics: an athletic contest modeled after the Olympic Games but intended for mentally or physically handicapped persons
athletics: a contest between athletes

Other hypernyms of Special Olympics include athletic competition, athletic contest.

Special Olympics (noun)	athletics (noun)
an athletic contest modeled after the Olympic Games but intended for mentally or physically handicapped persons	an active diversion requiring physical exertion and competition
	participation in sports events as an extracurricular activity
	a contest between athletes