goddam vs damn

goddam is not a noun while damn is a noun.

Word	Noun	Adjective	Verb	Adverb
goddam	No	Yes	No	Yes
damn	Yes	Yes	Yes	Yes

As adjectives, goddam and damn are synonyms defined as:

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

goddam (noun)	damn (noun)
	something of little value

goddam (adjective)	damn (adjective)
expletives used informally as intensifiers	used as expletives
	expletives used informally as intensifiers

goddam (verb)	damn (verb)
	wish harm upon; invoke evil upon

goddam (adverb)	damn (adverb)
expressing anger, despair, frustration, approval, or surprise	extremely