Music theory definition
Triad
A three-note chord stacked in thirds: root, 3rd, and 5th.
Hear an example
Play the example and listen for the idea described above.
Root, third, fifth
A = three stacked in 3rds: , 3rd, 5th.
Learn it in context
This term is introduced in Unit 8: Triads. Work through the explanations and exercises to connect the definition with music.
- Stacking thirds
How three notes make a chord.
Explore with an interactive tool
- Chord builder
Stack thirds, name the chord, and invert it. See it on the staff, keyboard, and fretboard.
Related music terms
- Voicing
- The way a chord’s notes are arranged: which is lowest and how far apart the others sit. The chord can keep its name while its voicing changes.
- Chord
- Three or more notes sounding together.
- Root
- The note a chord is built on and named after.
- Chord quality
- Major, minor, diminished, or augmented - set by the sizes of the 3rds in the chord.
- Chord inversion
- A chord with a note other than the root in the bass. First inversion has the 3rd in the bass; second has the 5th.
- Root position
- A chord with its root as the lowest note.