goddamn vs damned

goddamn is not a noun while damned is a noun.

Word	Noun	Adjective	Verb	Adverb
goddamn	No	Yes	No	Yes
damned	Yes	Yes	No	Yes

As adjectives, goddamn and damned are synonyms defined as:

Other synonyms of goddamn include blame, blamed, blasted, blessed, damn, darned, deuced, goddam, goddamned, infernal.

goddamn (noun)	damned (noun)
	people who are condemned to eternal punishment

goddamn (adjective)	damned (adjective)
used as expletives	expletives used informally as intensifiers
expletives used informally as intensifiers	in danger of the eternal punishment of Hell

goddamn (adverb)	damned (adverb)
expressing anger, despair, frustration, approval, or surprise	in a damnable manner