\Di`a*ton"ic\, a. [L. diatonicus, diatonus, Gr. ?, ?,
fr. ? to stretch out; dia` through + ? to stretch: cf. F.
diatonique. See {Tone}.] (Mus.)
Pertaining to the scale of eight tones, the eighth of which
is the octave of the first.
{Diatonic scale} (Mus.), a scale consisting of eight sounds
   with seven intervals, of which two are semitones and five
   are whole tones; a modern major or minor scale, as
   distinguished from the {chromatic} scale.