1. (n.) A sweet or agreeable succession of sounds.

2. (n.) A rhythmical succession of single tones, ranging for the most part within a given key, and so related together as to form a musical whole, having the unity of what is technically called a musical thought, at once pleasing to the ear and characteristic in expression.

3. (n.) The air or tune of a musical piece.

air aria bel canto canto cantus descant diapason dulcetness euphoniousness euphony harmony lay line lyrics measure mellifluence mellifluousness melodia melodic line melodiousness musical quality musical sound musicality note refrain solo solo part song soprano part strain sweetness theme tonality tone treble tune tunefulness warble