Guitar music theory glossary

Terms

accidental

A sharp (♯), flat (♭) or natural sign that raises, lowers or restores a note.

arpeggio

A chord played one note at a time instead of all together.

augmented

A chord with a major 3rd and a raised 5th, written +. Its notes split the octave into three equal parts.

barre chord

A chord where one finger presses several strings at the same fret, like a movable nut, so the shape works anywhere on the neck.Also called barre

blues scale

The minor pentatonic with one extra note, the ♭5 (also written ♯4), that gives the blues its bite.

borrowed chord

A chord taken from the parallel key, such as B♭ (♭VII) or Fm (iv) in C major, borrowed from C minor.

cadence

A chord move that ends a phrase, like a punctuation mark. V to I is the strongest, a full stop.

CAGED

A way of mapping the fretboard with the five open chord shapes C, A, G, E and D, moved up the neck to play any chord.

capo

A clamp across all six strings at one fret. It raises every open string, so familiar shapes play in a higher key.

chromatic

Using notes from outside the key, or moving by half steps through all twelve notes.

circle of fifths

All twelve keys arranged in a circle, each a 5th above the last. Neighbouring keys differ by one sharp or flat.

diatonic

Using only the seven notes of the key. The diatonic chords are the seven chords you can build from those notes.

diminished

A chord with a minor 3rd and a flattened 5th, written °. It sounds tense, and is the vii° chord of a major key.

diminished 7th

Four notes stacked in minor 3rds, written °7. Every note is the same distance from the next, so the chord pulls hard to the chord a half step above any of its notes.Also called diminished seventh

dominant

The 5th degree of a key and the chord on it (V). It creates tension that wants to resolve home to the tonic.

dominant 7th

A major chord with a minor 7th added, such as G7. It is the V7 of a key and pulls strongly to the I chord.Also called dominant seventh

enharmonic

Two names for the same sound, such as F♯ and G♭. They are played on the same fret but spelled differently.

extended chord

A chord that keeps stacking 3rds past the 7th, adding the 9th, 11th or 13th: C9, Am11 and G13. Players keep the 3rd, the 7th and the top note and drop the 5th first.

fret

The metal strips across the neck, and the spaces between them. Each fret raises a string by one half step.

half step

The smallest distance in Western music: one fret on the guitar, such as E to F or F to F♯.Also called semitone, semitones

half-diminished

A diminished triad with a minor 7th added, written m7♭5 or ø7. It is the ii chord of a minor key.

hammer-on

Sounding a higher note by bringing a finger down hard on the string without picking it again.

harmonic minor

The natural minor scale with its 7th raised a half step, which makes the V chord major and gives it a strong pull home.

interval

The distance between two notes, counted in letter names (a 3rd, a 5th) and in half steps (a major 3rd is four).

key signature

The sharps or flats written at the start of each line of music, telling you which notes the key changes.

leading note

The 7th degree of a major or harmonic minor scale, a half step below the tonic. It pulls up strongly to the home note.Also called leading tone

modulation

Changing key within a piece of music, so a different note becomes home.Also called modulate, modulates, key change

movable shape

A chord or scale fingering with no open strings. Slide it up or down the neck and it changes its root but not its type: a major shape stays major.

Nashville number system

Chord charts written with plain numbers for the degrees of the key (1 4 5 6m), so a song can be played in any key.Also called Nashville numbers

natural minor

The minor scale with the same notes as its relative major: in A minor, A B C D E F G.

nut

The slotted strip at the top of the neck where the strings leave the headstock. Open strings ring from the nut.

octave

The distance of twelve half steps, where a note comes round to the same name. Twelve frets up a string is an octave.

open chord

A chord played near the nut that uses some unfretted strings, such as the open G, C or Em.Also called open shape, open shapes

palm mute

Resting the side of the picking hand on the strings near the bridge for a short, chunky sound.Also called palm-muted

parallel minor

The major and minor keys that share a tonic but not all their notes, such as C major and C minor.Also called parallel major, parallel key, parallel keys

pentatonic

A five-note scale. The minor pentatonic is the most used scale in rock and blues guitar solos.

pivot chord

A chord that belongs to both the old key and the new one, used to slip smoothly from one to the other.

power chord

Just the root and the 5th, often with the root doubled: C5 is C and G. With no 3rd it is neither major nor minor, which keeps it clear under distortion.

predominant

A chord whose job is to lead to the dominant, usually ii or IV. It moves the music away from home.

pull-off

Sounding a lower note by flicking a fretting finger off the string, without picking it again.

relative minor

The major and minor keys that share all seven notes and the same key signature, such as C major and A minor.Also called relative major, relative key, relative keys

Roman numeral

A chord written by its place in the key: upper case for major (IV), lower case for minor (vi), ° for diminished.Also called numeral, numerals

root

The note a chord is named after and built up from. C is the root of C, Cm and C7.

scale degree

A note's number within its scale, counted from the tonic: in C major, E is the 3rd degree and G the 5th.

secondary dominant

The V chord of a chord other than the tonic, borrowed for extra pull: in C major, E is V/vi and leads to Am.

seventh chord

A triad with one more 3rd on top, the 7th, which makes four notes: G7, Cmaj7 and Am7 are seventh chords.Also called 7th chord, 7th chords

slash chord

A chord with a different note in the bass, written after a slash: C/E is a C chord with E as its lowest note. The letter after the slash is the bass.

subdominant

The 4th degree of a key and the chord on it (IV). It moves away from home, often on the way to V.

suspended

A chord that replaces its 3rd with a 2nd (sus2) or a 4th (sus4), so it is neither major nor minor and sounds unresolved.Also called sus chord, sus chords

time signature

The two numbers at the start of the music: how many beats in a bar, and which note value gets one beat. 4/4 is the most common.

tonic

The home note of a key, and the chord built on it. Music in G major feels finished when it lands on G.

transpose

Moving a song to a different key by shifting every chord by the same distance.

triad

A three-note chord stacked in 3rds: a root, a 3rd and a 5th. Major, minor, diminished and augmented chords are triads.

tritone

The interval of six half steps, exactly half an octave, such as B to F. It is the tense heart of a dominant 7th chord.

vibrato

A fast, small wobble in pitch, made by rocking or bending the fretting finger, that makes a held note sing.

voicing

One particular way to arrange a chord's notes on the strings. Every chord has several voicings up the neck.

whole step

Two half steps, or two frets on the guitar, such as C to D.Also called whole tone, whole tones