Source : Webster's Revised Unabridged Dictionary (1913)

Affix \Af"fix\, n.; pl. {Affixes}. [L. affixus, p. p. of
   affigere: cf. F. affixe.]
   That which is affixed; an appendage; esp. one or more letters
   or syllables added at the end of a word; a suffix; a postfix.

Affix \Af*fix"\, v. t. [imp. & p. p. {Affixed}; p. pr. & vb. n.
   {Affixing}.] [LL. affixare, L. affixus, p. p. of affigere to
   fasten to; ad + figere to fasten: cf. OE. affichen, F.
   afficher, ultimately fr. L. affigere. See {Fix}.]
   1. To subjoin, annex, or add at the close or end; to append
      to; to fix to any part of; as, to affix a syllable to a
      word; to affix a seal to an instrument; to affix one's
      name to a writing.

   2. To fix or fasten in any way; to attach physically.

            Should they [caterpillars] affix them to the leaves
            of a plant improper for their food.   --Ray.

   3. To attach, unite, or connect with; as, names affixed to
      ideas, or ideas affixed to things; to affix a stigma to a
      person; to affix ridicule or blame to any one.

   4. To fix or fasten figuratively; -- with on or upon; as,
      eyes affixed upon the ground. [Obs.] --Spenser.

   Syn: To attach; subjoin; connect; annex; unite.

Source : WordNet®

affix
     n : a linguistic element added to a word to produce an inflected
         or derived form
     v 1: attach to; "affix the seal here" [syn: {stick on}]
     2: add to the very end; "He appended a glossary to his novel
        where he used an invented language" [syn: {append}, {add
        on}, {supplement}]
     3: attach or become attached to a stem word; "grammatical
        morphemes afix to the stem"