Glossary

The music-theory terms used across the site, explained in plain language.

Arpeggio

Playing the notes of a chord one at a time instead of all together. It lets you hear each note clearly — and it is a musical device in its own right.

Barre

When one finger — usually the index of your fretting hand — presses several strings at once on the same fret. It takes strength at first; practice makes it routine.

Degree

A note's (or chord's) position inside the scale, counted from the tonic: the 1st degree is the tonic itself, the 5th is the fifth note, and so on.

Dominant

The chord built on the fifth degree of the key, usually with a seventh. Its job is to create tension and ask for the return to the home chord — it is the engine of harmonic motion.

Fifth

The fifth note counting from the root (which counts as 1). It stabilizes the chord — the frame that holds the picture.

Guide notes

The third and the seventh of the chord — the two notes that most define its color. In solos and arrangements, they are the ones telling the story.

Half step

The smallest distance between two notes in Western music. On the fretboard, it is the difference of one fret.

ii–V–I

Jazz's most-used chord sequence: the second degree prepares the fifth, which resolves to the first. Question, suspense and answer — in three chords.

Interval

The distance between two notes. It is harmony's basic unit: every chord and scale sounds the way it does because of the intervals it contains.

Open string

A string played with no finger pressing the neck. It rings at the instrument's natural tuning — and makes the chord easier.

Root

The note that names the chord — its "surname". In C, Cm or C7 the root is always C; every other note is counted from it.

Scale

An ordered sequence of notes that melodies and improvisation are built on. Each scale has its own pattern of distances — and that pattern is the flavor.

Seventh

A fourth note added to the basic chord: the seventh note counting from the root (which counts as 1). The minor seventh creates motion; the major, smoothness.

Seventh chord

The triad plus a fourth note, the seventh. In other words: the same chord, now richer — Cmaj7 is C's seventh chord.

Third

The third note counting from the root — the note that names the chord counts as 1. It sets the mood: a major third sounds open; a minor third sounds serious.

Triad

The basic three-note chord: root, third and fifth. It is the smallest formation that already sounds like a complete chord.

Tritone

The distance of three whole steps between two notes — the most unstable interval in tonal music. It creates the "this needs to resolve" feeling in seventh chords.

Vamp

A short one- or two-chord loop that repeats for a long stretch, creating a mood instead of a journey — common in funk, reggae and modal music.

Voicing

A specific way to build the same chord on the neck — which notes go in, in what order and register. C has dozens of voicings; the name stays, the shape changes.

Updated July 9, 2026