rock climbing vs athletics

rock climbing and athletics both are nouns.

Word	Noun	Adjective	Verb	Adverb
rock climbing	Yes	No	No	No
athletics	Yes	No	No	No

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

rock climbing: the sport or pastime of scaling rock masses on mountain sides (especially with the help of ropes and special equipment)
athletics: an active diversion requiring physical exertion and competition

Other hypernyms of rock climbing include climb, mount, sport.

rock climbing (noun)	athletics (noun)
the sport or pastime of scaling rock masses on mountain sides (especially with the help of ropes and special equipment)	an active diversion requiring physical exertion and competition
	participation in sports events as an extracurricular activity
	a contest between athletes