wrestler vs grappler

wrestler and grappler both are nouns.

Word	Noun	Adjective	Verb	Adverb
wrestler	Yes	No	No	No
grappler	Yes	No	No	No

As nouns, wrestler and grappler are synonyms defined as:

wrestler and grappler: combatant who tries to throw opponent to the ground

Other synonyms of wrestler include matman.

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