augmented

An augmented interval is one semitone larger than a major or perfect interval. The augmented fifth — spanning eight semitones — creates the distinctive whole-tone-like sound of the augmented triad. An augmented chord consists of two stacked major thirds, dividing the octave into three equal parts. Like the diminished chord, the augmented chord is symmetrical — there are only four distinct augmented triads, and each can resolve in multiple directions. This ambiguity makes augmented chords useful for modulation and creating a sense of harmonic suspension. Debussy and other impressionist composers used augmented chords extensively for their floating, unresolved quality.