A series of two or more grace notes played before the principal note. This ornament usually consists of the principal note, the note below, and the principal note again. an ornament consisting of a single alternation between a given pitch, and the one immediately below or above it-- called an inverted mordent. Rapidly play the principal note, the next higher note (according to key signature) then return to the principal note for the remaining duration. In much music, the mordent begins on the auxiliary note, and the alternation between the two notes may be extended.