Diatonic and chromatic

Diatonic (Greek:διατονική) and chromatic (Greek:χρωματική) are terms in music theory that are most often used to characterize scales, and are also applied to musical instruments, intervals, chords, notes, musical styles, and kinds of harmony. They are very often used as a pair, especially when applied to contrasting features of the common practice music of the period 1600–1900.