Chord (music)

Overview

A chord is a collection of three or more distinct pitches sounded simultaneously, or perceived as sounding together, that functions as a single harmonic unit. The most common chords are built from stacked thirds, producing triads (three‑note chords) and seventh chords (four‑note chords), but chords can also arise from other intervallic constructions such as suspended, added‑tone, or altered chords. In tonal music, chords are labeled by their root note and quality (major, minor, diminished, augmented) and are organized into progressions that convey tension and resolution.

Chords are not limited to any single instrument; they appear in piano voicings, guitar strumming patterns, orchestral textures, and vocal harmony. While the term often evokes Western tonal harmony, chords also exist in non‑Western and contemporary music, where they may be constructed from modal or synthetic scales. Understanding chords is essential for composition, improvisation, analysis, and aural training.

History / Origin

The word “chord” derives from the Old French corde, meaning “string,” which in turn comes from the Latin chorda. In early music theory, the concept of sounding multiple notes together was described as “consonance” rather than a distinct chord. By the late 16th and early 17th centuries, theorists such as Gioseffo Zarlino began to codify triadic structures, and the term “accord” (the French equivalent) entered the musical lexicon. The English spelling “chord” became standard in the 18th century alongside the rise of functional harmony in the works of J.S. Bach and later Classical composers.

How It’s Used

Chords appear in virtually every genre. In classical music they underpin cadences and form the basis of sonata‑type structures; in jazz they serve as the framework for improvisation, often extended with ninths, thirteenths, and alterations. Pop, rock, and folk songs typically rely on simple triadic progressions (e.g., I‑V‑vi‑IV) that are notated in lead sheets or chord charts. Guitarists use chord diagrams, pianists employ staff notation with stacked noteheads, and composers may write chord symbols above the staff for quick harmonic reference. Roman‑numeral analysis is a common method for describing chord functions relative to a key.

Why It Matters

Chords provide the harmonic context that shapes melody, rhythm, and emotional impact. A major chord often conveys brightness or stability, while a minor chord can suggest melancholy or tension. The progression from a dominant seventh to the tonic (V7–I) is a cornerstone of Western tonal resolution, heard in countless works from Beethoven’s symphonies to modern pop hits like The Beatles’ “Let It Be.” Mastery of chords enables musicians to compose compelling progressions, improvise fluidly, and analyze the structure of existing repertoire.

Common Misconceptions