lacrosse player vs jock

lacrosse player and jock both are nouns.

Word	Noun	Adjective	Verb	Adverb
lacrosse player	Yes	No	No	No
jock	Yes	No	No	No

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

Other hypernyms of lacrosse player include athlete, participant, player.

lacrosse player (noun)	jock (noun)
an athlete who plays lacrosse	a support for the genitals worn by men engaging in strenuous exercise
	a person trained to compete in sports