What is "cranberry morpheme"

n. (context linguistics English) A bound morpheme within a complex word which is a http://en.wikipedia.org/wiki/Fossilization%20(linguistics) and whose meaning is opaque to the present speakers of the language. May refer narrowly to morphemes which occur in a single word, or more broadly to fossilized morphemes generally.

In linguistic morphology, a cranberry morpheme (or fossilized term) is a type of bound morpheme that cannot be assigned an independent meaning or grammatical function, but nonetheless serves to distinguish one word from the other.