This article is about an eleventh in music theory. For the chord, see Eleventh chord. For the character, see Eleventh Doctor. For the century, see 11th century. For the US constitution amendment, see Eleventh Amendment to the United States Constitution.
In music or music theory an eleventh play (help·info) 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.
