Morion

The morion (plural: moria) is a unit of interval size equivalent to 1 step of 72edo.

6 moria make 1 degree of 12edo.

72edo is useful as a fine-grain interval size measure, particularly in barbershop harmony, wherein 1, 2, and 3 moria represent 'small', 'medium' and 'large' adjustments from 12edo in microtuning of harmony parts to 7-limit JI. 1 morion takes, for example, 16/9 to 9/5, via 81/80; 2 moria takes, for example, 16/9 to 7/4, via 64/63; and 3 moria takes, for example, 9/5 to 7/4, via 36/35.

72edo is also fantastic in the 11-limit, and provides a great framework for extending barbershop harmony to the 11-limit, where the large adjustment (3 moria) already familiar to harmony singers may also take, for example, 4/3 to 11/8, via 33/32, and the medium adjustment (2 moria) may also take, for example, 9/5 to 11/6, or 15/8 to 11/6, via 55/54 or 45/44 respectively.

1 morion is exactly 170.5 primas.