Schisma

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In music, the schisma (also spelled skhisma) is the interval between the syntonic comma (81:80) and the Pythagorean comma ( 531 441 : 524 288 ), which is slightly larger. It equals ⁠ 5 × 38 / 215 ⁠ or 32 805 : 32 768 ≈ 1.00113, which corresponds to 1.9537 cents. It may also be defined as:the difference (in cents) between 8 justly tuned perfect fifths plus a justly tuned major third and 5 octaves; the ratio of major limma to the Pythagorean limma; the ratio of the syntonic comma and the diaschisma.

Summary from Wikipedia