In music and tuning, the ragisma is an interval with the ratio of 4375:4374, ≈0.396 cents (a superparticular ratio). It is usually defined as the difference between the septimal minor third (7:6) and two Bohlen–Pierce small semitones (27:25
- Haluska, Jan (2003). The Mathematical Theory of Tone Systems, p.xxviii. ISBN 80-88683-28-9.