Descant

Descant or discant can refer to several different things in music, depending on the period in question; etymologically, the word means a voice (cantus) above or removed from others.

A discant (occasionally, particularly later, written descant) is a form of medieval music in which one singer sang a fixed melody, and others accompanied with improvisations. The word in this sense comes from the term discantus supra librum (descant "by the book"), and is a form of Gregorian chant in which only the melody is notated but an improvised polyphony is understood. The discantus supra librum had specific rules governing the improvisation of the additional voices.

Later on, the term came to mean, the treble or soprano singer in any group of voices, or the higher pitched line in a song, and eventually, by the Renaissance, referred generally to counterpoint.

Descant can also refer to the highest pitched of a group of instruments, particularly the descant viol or recorder. Similarly, it can also be applied to the soprano clef.Descant could also refer to a high, florid melody sung by a few sopranos as a decoration for a hymn.