Clitic
Part of speech: noun
Definition: A morpheme that functions like a word, but appears not as an independent word but rather is always attached to a following or preceding word. In English, the possessive -'s is an example.
Affix
Part of speech: verb
Definition: To attach.
Part of speech: noun
Definition: That which is affixed; an appendage.A bound morpheme added to a word's stem; formerly applied only to suffixes (also called postfixes), the term as now used comprises prefixes, suffixes, infixes, circumfixes, and suprafixes.The complex number a+bi associated to the point in the Gauss Plane with coordinates (a,b).