interval
F major seventh
FlowerEupperM711 half steps
Eleven half steps: a half step short of the octave, which is why it leans on it.
On the keyboard
What is true of it
F up a major seventh is E: 11 half steps, and 7 letters counting both ends.
Turn it upside down — put the F on top — and it becomes a minor second. The two numbers always add to nine, and the two sizes to twelve.
It is a dissonance.
Every interval on F
F → G♭minor second · dissonanceF → Gmajor second · dissonanceF → A♭minor third · imperfect consonanceF → Amajor third · imperfect consonanceF → B♭perfect fourth · perfect consonanceF → Baugmented fourth · dissonanceF → C♭diminished fifth · dissonanceF → Cperfect fifth · perfect consonanceF → D♭minor sixth · imperfect consonanceF → Dmajor sixth · imperfect consonanceF → E♭minor seventh · dissonance