affix

1 grammar :  one or more sounds or letters occurring as a bound form attached to the beginning or end of a word, base, or phrase or inserted within a word or base and serving to produce a derivative word or an inflectional form The affix in the word “attendance” is “-ance.”

2 :  appendage

1 :  to attach firmly Affix the stamp to the envelope.

2 :  to add to something else He affixed his signature to the letter.

:  a letter or group of letters (as a prefix or suffix) that comes at the beginning or end of a word and has a meaning of its own

1 :  to attach physically

2 :  to attach or add in any way affix a signature to a document

3 :  to make by or as if by pressure affix my seal