annex vs affix

annex and affix both are nouns.

Word	Noun	Adjective	Verb	Adverb
annex	Yes	No	Yes	No
affix	Yes	No	Yes	No

As verbs, affix is a hypernym of annex; that is, affix is a word with a broader meaning than annex:

Other hypernyms of annex include add on, append, supplement.

annex (noun)	affix (noun)
an addition that extends a main building	a linguistic element added to a word to produce an inflected or derived form

annex (verb)	affix (verb)
add an extra part to	stick or fasten to
take (territory) as if by conquest	add to the very end
	attach or become attached to a stem word