unfriendly vs combining form

unfriendly is not a noun while combining form is a noun.

Word	Noun	Adjective	Verb	Adverb
unfriendly	No	Yes	No	No
combining form	Yes	No	No	No

unfriendly (noun)	combining form (noun)
	a bound form used only in compounds

unfriendly (adjective)	combining form (adjective)
not disposed to friendship or friendliness
not easy to understand or use
very unfavorable to life or growth
not friendly