||A*pot"o*me (&?;), n. [Gr. &?; a cutting off, fr. &?; to cut off; &?; from + &?; to cut.] 1. (Math.) The difference between two quantities commensurable only in power, as between √2 and 1, or between the diagonal and side of a square.

2. (Mus) The remaining part of a whole tone after a smaller semitone has been deducted from it; a major semitone. [Obs.]