Eleventh
| Inverse | perfect fifth |
|---|---|
| Name | |
| Other names | compound fourth |
| Abbreviation | P11 |
| Size | |
| Semitones | 17 |
| Cents | |
| Equal temperament | 1700.0 |
| Inverse | diminished fifth |
|---|---|
| Name | |
| Abbreviation | A11 |
| Size | |
| Semitones | 18 |
| Cents | |
| Equal temperament | 1800.0 |
In music or music theory an eleventh 
play is the note eleven scale degrees from the root of a chord and also the interval between the root and the eleventh. The interval can be also described as a compound fourth, spanning an octave plus a fourth.
Since there are only seven degrees in a diatonic scale the eleventh degree is the same as the subdominant.
The eleventh is considered highly dissonant with the third.
A perfect eleventh is an eleventh which spans exactly 17 semitones. It can be also described as a compound perfect fourth, spanning an octave plus a perfect fourth.
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