amateur vs jock

amateur and jock both are nouns.

Word	Noun	Adjective	Verb	Adverb
amateur	Yes	Yes	No	No
jock	Yes	No	No	No

As nouns, jock is a hypernym of amateur; that is, jock is a word with a broader meaning than amateur:

Other hypernyms of amateur include athlete.

amateur (noun)	jock (noun)
someone who pursues a study or sport as a pastime	a support for the genitals worn by men engaging in strenuous exercise
an athlete who does not play for pay	a person trained to compete in sports

amateur (adjective)	jock (adjective)
engaged in as a pastime
lacking professional skill or expertise