Text: The distance in pitch between two notes, which is expressed in terms of the number of notes of the diatonic scale which they comprise (e.g. third, fifth, ninth) and a qualifying word (perfect, imperfect, major, minor, augmented, or diminished). The number is determined by the position of the notes on the staff, the qualifying word by the number of tones and semitones in the interval. Thus (no clef) C - G is always a third, while (F clef) C - G is a major third, being a distance of two tones, and (G clef) C - G is a minor third, being a distance of a tone and a half.

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