sulfurous vs American spelling

sulfurous is not a noun while American spelling is a noun.

Word	Noun	Adjective	Verb	Adverb
sulfurous	No	Yes	No	No
American spelling	Yes	No	No	No

sulfurous (noun)	American spelling (noun)
	English orthography used in the United States (characterized by 'analyze', 'center', 'usable')

sulfurous (adjective)	American spelling (adjective)
of or related to or containing sulfur or derived from sulfur
characterized by oppressive heat and humidity
harsh or corrosive in tone