downward vs American English

downward is not a noun while American English is a noun.

Word	Noun	Adjective	Verb	Adverb
downward	No	Yes	No	Yes
American English	Yes	No	No	No

downward (noun)	American English (noun)
	the English language as used in the United States

downward (adjective)	American English (adjective)
extending or moving from a higher to a lower place
on or toward a surface regarded as a base

downward (adverb)	American English (adverb)
spatially or metaphorically from a higher to a lower level or position