Sing, troll, carol, descant, warble, trill, hymn, chant, intone all mean to produce musical tones by or as if by means of the voice.
Sing is the general term used of human beings and of animals and things that produce musical or sustained tones. In its primary application to human beings it usually implies utterance in words with musical inflections or modulations and often suggests such modulated utterance as an art to be practiced, studied, or learned.
Troll usually suggests the use of full round tones in singing and is especially applicable to the hearty voices of jovial men raised in singing or the resonant celebration in song of great events or deeds.
Carol suggests the voices of youthful, lively, or joyous singers, usually of persons, sometimes of birds; it may or may not suggest the singing of carols, but it often implies merriment or effortlessness and spontaneity.
Descant (see also DISCOURSE ) implies part singing or, especially, the singing of a higher part in harmony with the plainsong of the tenor in a contrapuntal treatment. Descant often merely implies harmonious singing or singing in harmony with.
Warble frequently implies singing in a soft and gentle voice but with various modulations (as turns and trills and quavers); often it means no more than to sing melodiously or with sweetness.
Trill basically means to sing with trills or vibrations (as by rapidly alternating two notes a degree apart), but it is often extended to refer to the making of sounds involving vibration without much thought of musical quality.
Hymn implies a lifting of the voice in songs of worship or praise, especially of God.
Chant may mean little more than sing, but often it is used specifically to imply the method of singing adopted by priests or choristers singing unmetrical verse where the emphasis is upon musical recitation of phrases, measured even tones, and a reverential spirit.
Intone also comes very close to the specific sense of chant in meaning but sometimes carries a stronger connotation of reciting in sustained monotone.