combined vs one

combined is not a noun while one is a noun.

Word	Noun	Adjective	Verb	Adverb
combined	No	Yes	No	No
one	Yes	Yes	No	No

combined (noun)	one (noun)
	a single person or thing
	the smallest whole number or a numeral representing this number

combined (adjective)	one (adjective)
made or joined or united into one	used of a single unit or thing; not two or more
	being a single entity made by combining separate components
	(informal) very; used informally as an intensifier
	eminent beyond or above comparison
	indefinite in time or position
	of the same kind or quality
	having the indivisible character of a unit