destructive vs caustic

destructive is not a noun while caustic is a noun.

Word	Noun	Adjective	Verb	Adverb
destructive	No	Yes	No	No
caustic	Yes	Yes	No	No

destructive (noun)	caustic (noun)
	the envelope of light rays reflected or refracted by a curved surface or object
	any chemical substance that burns or destroys living tissue

destructive (adjective)	caustic (adjective)
causing destruction or much damage	of a substance, especially a strong acid; capable of destroying or eating away by chemical action
	harsh or corrosive in tone