dampening; muting: A silencing effect created by touching strings to prevent them from ringing out clearly.

decay: Part of an instrument's tone color that is heard in the final part of the played note.

desiccant: A powder or crystal substance that draws humidity out of the air, lowering the local relative humidity level.

distortion: A guitar effect that produces a fuzzy sound, as if the signal was too powerful for the amp.

dominant 7th chords: A chord built from the first, third, fifth, and flatted seventh note of a scale. In a major scale, a seventh chord built from the fifth note of the scale is naturally a dominant seventh chord.

double-stop: The fretting and playing of two strings simultaneously.

doubling: A technique for creating power chords by playing the same notes in different octaves on different strings.

downstrokes: 1. A musical notation often shaped like an open-bottomed box that indicates that the note or chord should be played with a downward motion of the pick. 2. Dragging your pick (or thumb) across the strings toward the floor as you play.

dynamics: The volume at which notes are played.