3 Chord names and symbols – Introduction to Music Theory

All chords are named by their roots. They can be labeled in several ways:

By letter name of the root
By scale-degree name of the root
By Roman numeral of the root

Letter name
A chord built on A (A-C-E) is called an A chord; from B (B-D-F), a B chord; and so on. This was demonstrated at the beginning of this lesson.

Scale-degree name
Each scale step and its corresponding chord have a name that indicates their relationship to the tonic, the name of the main tone of a key. These names were first introduced in Lesson 3.

Scale-degree and chord name:
1	tonic	the central pitch that the other pitches “gravitate” toward
2	supertonic	the note above (“super”) tonic; often moves down one step to tonic in melodies
3	mediant	the note midway between tonic and the dominant above
4	subdominant	the note below (“sub”) the dominant; often moves up to the dominant
5	dominant	after tonic, the most important pitch of a key; often moves directly to tonic
6	submediant	the note midway between tonic and the subdominant below
7	leading tone or subtonic	the note 1/2 step below tonic; often “leads” directly to tonic the note below tonic (whole step below tonic)

Roman numeral
Roman numerals are used to represent each chord constructed above the pitches of a scale. These Roman numerals are very efficient for precisely labeling chords. They show how a particular chord functions within a tonality (by relating to scale-degree numbers) as well as the quality of the chord (uppercase vs. lowercase).

Uppercase numerals are used for major chords (e.g., I).

Lowercase numerals are used for minor chords (e.g., vi).

Lowercase numerals with a small superscript “o” are used for diminished chords (e.g., viiº ).

Uppercase numerals with a small superscript plus sign “+” are used for augmented chords (e.g., III+)

Following are the chord symbols and chord names for the major scale and all three forms of the minor scale. It is not necessary to memorize the qualities of each chord in any of the scales. You can always figure that out by thinking/writing the chord within the key of C major or A minor. Determine the quality of the chord and finally use the correct version of the Roman numeral to match.

Major scale
*Scale degree*	*Chord symbol*	*Chord name*

1	I	tonic
2	ii	supertonic
3	iii	mediant
4	IV	subdominant
5	V	dominant
6	vi	submediant
7	viiº	leading tone

Major scale triads:

Natural minor scale
*Scale degree*	*Chord symbol*	*Chord name*

1	i	tonic
2	iiº	supertonic
3	III	mediant
4	iv	subdominant
5	v	“minor” dominant
6	VI	submediant
7	VII	subtonic

Natural minor scale triads:

Harmonic minor scale
*Scale degree*	*Chord symbol*	*Chord name*

1	i	tonic
2	iiº	supertonic
3	III+	mediant
4	iv	subdominant
5	V	dominant
6	VI	submediant
7	viiº	leading tone

Harmonic minor scale triads:

Melodic minor scale (ascending)
*Scale degree*	*Chord symbol*	*Chord name*

1	i	tonic
2	ii	supertonic
3	III+	mediant
4	IV	subdominant
5	V	dominant
6	viº	submediant
7	viiº	leading tone

Melodic minor scale triads:

In the minor mode, the chords found in the harmonic form of the scale are the ones most commonly used in harmony (thus, “harmonic minor” scale). Following are the most significant changes between the natural minor chords and harmonic minor chords:

Notice how the following triad can be labeled in the key of F major and d minor. In example A, the chord is simply labeled by its root (D) and quality (minor). In B, the chord is labeled by its name within the key (submediant in the key of F major and tonic within the key of d minor). And finally in C, the chord is labeled by a Roman numeral. Notice how the Roman numeral symbols reflect both the scale-degree name AND the quality of the triad.

Three methods to label chords:

As can be seen, a d minor triad functions differently within the key of F major and d minor.

Challenge yourself:

Question:
In what major and minor keys do you find a d minor triad? List them by key and Roman numeral. Hint–A d minor triad will always be minor and labeled with a lowercase Roman numeral.

Use the tables above for help before looking at the answer.