Olympiad vs athletics

Olympiad and athletics both are nouns.

Word	Noun	Adjective	Verb	Adverb
Olympiad	Yes	No	No	No
athletics	Yes	No	No	No

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

Olympiad: the modern revival of the ancient games held once every 4 years in a selected country
athletics: a contest between athletes

Other hypernyms of Olympiad include athletic competition, athletic contest.

Olympiad (noun)	athletics (noun)
the modern revival of the ancient games held once every 4 years in a selected country	an active diversion requiring physical exertion and competition
one of the four-year intervals between Olympic Games; used to reckon time in ancient Greece for twelve centuries beginning in 776 BC	participation in sports events as an extracurricular activity
	a contest between athletes