A cranberry morpheme, according to Andrew Spencer in the book Morphological Theory, is a morpheme that has "neither meaning nor grammatical function, yet is used to differentiate one word from another". The term cranberry morpheme was chosen to describe this linguistic occurrence based on the comparison of the word 'cranberry' to other 'berry' words where the first morphemes do carry meaning (ex. blueberry, blackberry and loganberry).Cranberry morphemes are sometimes called "fossilized terms". In the case of the word 'cranberry' Wikipedia points out the fact that 'cran' "actually comes from crane (the bird)." Of course this etymology is not commonly known, thus the alternate name "fossilized term".
Some cranberry morphemes with 'tude' that are currently popular include:
Prefixes
celebu-
nano-
mongo-
Suffixes
-isode
-cation
-rexia
-dango
-palooza
