In
classical music from
Western culture, a
third is a
musical interval encompassing three
staff positions (see
Interval number for more details), and the
major third is a third spanning four
semitones. Along with the
minor third, the major third is one of two commonly occurring thirds. It is qualified as
major because it is the larger of the two: the major third spans four semitones, the
minor third three. For example, the interval from C to E is a major third, as the note E lies four semitones above C, and there are three staff positions from C to E.
Diminished and
augmented thirds span the same number of staff positions, but consist of a different number of semitones (two and five).