grappling hook vs grappler

grappling hook and grappler both are nouns.

Word	Noun	Adjective	Verb	Adverb
grappling hook	Yes	No	No	No
grappler	Yes	No	No	No

As nouns, grappling hook and grappler are synonyms defined as:

grappling hook and grappler: a tool consisting of several hooks for grasping and holding; often thrown with a rope

Other synonyms of grappling hook include grapnel, grapple, grappling iron.

grappling hook (noun)	grappler (noun)
a tool consisting of several hooks for grasping and holding; often thrown with a rope	a tool consisting of several hooks for grasping and holding; often thrown with a rope
	combatant who tries to throw opponent to the ground