Nouns

(n)affixa linguistic element added to a word to produce an inflected or derived form

Verbs

(v)affix, stick onstick or fasten to“affix the seal here”
(v)append, add on, supplement, affixadd to the very end“He appended a glossary to his novel where he used an invented language”
(v)affixattach or become attached to a stem word“grammatical morphemes affix to the stem”