US English orthography vs US English spelling

US English orthography and US English spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
US English orthography	Yes	No	No	No
US English spelling	Yes	No	No	No

As nouns, US English orthography and US English spelling are synonyms defined as:

US English orthography and US English spelling: English orthography used in the United States (characterized by 'analyze', 'center', 'usable')

Other synonyms of US English orthography include American English orthography, American English spelling, American spelling, US spelling.

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