grappling iron vs grappling hook

grappling iron and grappling hook both are nouns.

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

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

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

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

grappling iron (noun)	grappling hook (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