Glossary

Imitation

In counterpoint, the restatement of a theme, motif, or phrase in another part.

imperfect cadence

See half cadence.

impressionism

A stylistic period in music that coincides with the period of impressionistic painting, from the 1870s to early 1900s. Claude Debussy, Frederick Delius and Maurice Ravel were considered impressionistic composers. The music avoided traditional harmonic progressions, employing 9th, 11th and 13th chords, often doubling the melody in parallel “chord streams.”

impromptu

A short, improvisational-sounding piece.

improvisation

Spontaneous composition.

incidental music

Short musical segments that accompany or highlight dramatic moments in a play or other stage work.

instrumentation

The art of composing, orchestrating or arranging works for an instrumental ensemble.

interlude

A short piece that is used to bridge the acts of a play or the verses of a hymn.

introduction

The preparatory section, movement, or phrase of a musical work.

interval

The distance between two notes.

Introit

“Entrance.” A psalm (or psalm verse) sung at the beginning of the Roman Catholic Mass.

invention

A short, contrapuntal piece.

inversion

The different forms that a chord may take by changing the chord member that is the bass of the chord.

invertible counterpoint

counterpoint in which two or more voices can be interchanged.

Ionian

A medieval mode whose half- and whole-step pattern is that of playing C to C on the white keys of a piano.

Italian sixth

A type of augmented sixth chord containing a major third and an augmented sixth above the bass.