from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Describing a mode or scale that has seven pitches in an octave
from The Century Dictionary and Cyclopedia
- In music, consisting of seven tones to the octave: said of scales: often contrasted with pentatonic.
Now, with my own lips, I have played notes from Subterranean flutes twenty-five thousand years old standard diatonic to heptatonic, including a flatted la and a neutral third for mi, i.e., a blue note.
We have already remarked that the current medieval theory laid down for the tone system a heptatonic diatonic scale of about two octaves with the addition of b flat in the higher octave.