Museme

A museme is a minimal unit of musical meaning, analogous to a morpheme in linguistics, "the basic unit of musical expression which in the framework of one given musical system is not further divisible without destruction of meaning." A museme may:be broken down into component parts which are not in themselves meaningful within the framework of the musical language...but are nevertheless basic elements of musical expression which, when altered, may be compared to the phonemes of speech in that they alter the museme (morpheme) of which they are part and may thereby also alter its meaning.

Wikipedia →