descant

v. sing; sing in parts, harmonize

n. music with harmonizing melodies; melodies sung together

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.
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Noun
1. a decorative musical accompaniment (often improvised) added above a basic melody
(synonym) discant
(hypernym) accompaniment, musical accompaniment, backup, support
(derivation) yodel, warble
Verb
1. sing in descant
(hypernym) sing
(derivation) discant
2. sing by changing register; sing by yodeling; "The Austrians were yodeling in the mountains"
(synonym) yodel, warble
(hypernym) sing
(derivation) discant
3. talk at great length about something of one's interest
(hypernym) discourse, talk about, discuss

(v. i.)
To sing a variation or accomplishment.
  

(v. i.)
To comment freely; to discourse with fullness and particularity; to discourse at large.
  

(v. i.)
The upper voice in part music.
  

(v. i.)
The canto, cantus, or soprano voice; the treble.
  

(v. i.)
Originally, a double song; a melody or counterpoint sung above the plain song of the tenor; a variation of an air; a variation by ornament of the main subject or plain song.
  

(v. i.)
A discourse formed on its theme, like variations on a musical air; a comment or comments.
  

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