diatonic

An adjective referring to a scale composed of five tones and two semitones, such as the pythagorean diatonic or the familiar 12-tone version.

(Chalmers's second example is also referred to as a '7oo12' or '7-out-of-12' scale.)

"Diatonic" is an adjective used to refer to three different musical concepts:

• a type of scale,
• a specific type of semitone, and
• in ancient Greek music theory, a genus.