| Main Interval Name: | perfect eleventh |
| Inverse: | perfect fifth |
| Other Names: | Compound fourth |
| Abbreviation: | P11 |
| Semitones: | 17 |
| Cents Equal Temperament: | 1700.0 |
| Main Interval Name: | augmented eleventh |
| Inverse: | diminished fifth |
| Abbreviation: | A11 |
| Semitones: | 18 |
| Cents Equal Temperament: | 1800.0 |
In music or music theory, an eleventh 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 also be described as a compound fourth, spanning an octave plus a fourth.[1]
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 major third.
A perfect eleventh is an eleventh which spans exactly 17 semitones.