Originally (refering to the Hexachordum) "the wrong quinte"
It is the tone (or better - the interval) that divides the octave in exactly two halves -> 6:6 halftones OR 3:3 full tones (TRI=3 TONUS=tone/note). It was the Devil in music because it was quite difficult to explain the interval and also because of its dark sound AND - it does not exist in the overtone row.
Letz have a look at the proporions-theory of pythagoras. It is IMO one simple way of sorting the intervals from a tonal point of view.
Prim (unison) -> 1:1 (lat. primus="the first")
Octave -> 1:2
Quinte (fifth) -> 2:3
Quarte (fourth) -> 3:4
Majorem Sexte (major sixth) -> 3:5
Majorem Terz (Major third) -> 4:5
Minorem Terz (minor third) -> 5:6
Minorem Sexte (minor Sixth -> 5:8
Minorem Septime (minor seventh) -> 5:9
Majorem Sekunde (major second) -> 8:9
Majorem Septime (major seventh) -> 8:15
Minorem Sekunde (minor second) -> 15:16
Tritonus -> 32:45
As you can see the tritonus is a bit.. strange and this proportion does (unlike the others) not exist in the overtonerow.
-=[Azrael]=-
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