impressive vs heroic

impressive is not a noun while heroic is a noun.

Word	Noun	Adjective	Verb	Adverb
impressive	No	Yes	No	No
heroic	Yes	Yes	No	No

impressive (noun)	heroic (noun)
	a verse form suited to the treatment of heroic or elevated themes; dactylic hexameter or iambic pentameter

impressive (adjective)	heroic (adjective)
making a strong or vivid impression	relating to or characteristic of heroes of antiquity
producing a strong effect	having or displaying qualities appropriate for heroes
	showing extreme courage; especially of actions courageously undertaken in desperation as a last resort
	of behavior that is impressive and ambitious in scale or scope
	very imposing or impressive; surpassing the ordinary (especially in size or scale)