diatonic Meaning, Definition & Usage

  1. adjective based on the standard major or minor scales consisting of 5 tones and 2 semitones without modulation by accidentals
  2. adjective satellite based on or using the five tones and two semitones of the major or minor scales of western music

WordNet

Di`a*ton"ic adjective
Etymology
L. diatonicus, diatonus, Gr. , , fr. to stretch out; through + to stretch: cf. F. diatonique. See Tone.
Definitions
  1. (Mus.) Pertaining to the scale of eight tones, the eighth of which is the octave of the first.

Webster 1913