apotome

A*pot"o*me, n. Etym: [Gr. 1. (Math.) Defn: The difference between two quantities commensurable only in power, as between sq. root2 and 1, or between the diagonal and side of a square. 2. (Mus) Defn: The remaining part of a whole tone after a smaller semitone has been deducted from it; a major semitone. [Obs.]

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