musical scale made up of seven different tones. The major and minor scales of Western art music are the most commonly known heptatonic scales, but different forms of seven-tone scales exist. Medieval church modes, each having its characteristic pattern of whole and half steps, used seven tones. Scales that resemble the medieval modes are found in some European folk music. In Java, many forms of the seven-tone pelog scale occur. Heptatonic scales can also be found in the music of black Africa and of some American Indians.