grappling vs contact sport

grappling and contact sport both are nouns.

Word	Noun	Adjective	Verb	Adverb
grappling	Yes	No	No	No
contact sport	Yes	No	No	No

As nouns, contact sport is a hypernym of grappling; that is, contact sport is a word with a broader meaning than grappling:

grappling: the sport of hand-to-hand struggle between unarmed contestants who try to throw each other down
contact sport: a sport that necessarily involves body contact between opposing players

grappling (noun)	contact sport (noun)
the act of engaging in close hand-to-hand combat	a sport that necessarily involves body contact between opposing players
the sport of hand-to-hand struggle between unarmed contestants who try to throw each other down