grappling vs hand-to-hand struggle

grappling and hand-to-hand struggle both are nouns.

Word	Noun	Adjective	Verb	Adverb
grappling	Yes	No	No	No
hand-to-hand struggle	Yes	No	No	No

As nouns, grappling and hand-to-hand struggle are synonyms defined as:

grappling and hand-to-hand struggle: the act of engaging in close hand-to-hand combat

Other synonyms of grappling include grapple, wrestle, wrestling.

grappling (noun)	hand-to-hand struggle (noun)
the act of engaging in close hand-to-hand combat	the act of engaging in close hand-to-hand combat
the sport of hand-to-hand struggle between unarmed contestants who try to throw each other down