Carol

English Medieval strophic song with a refrain (called a burden) repeated after each stanza. Now, erroneously, any Christmas song is called a carol. an English genre which may have originated as a round dance. Texts could be in English, Latin, or both, and were frequently focussed on a joyful season: Easter, Christmas, or spring. The carol had a burden (the verses) and a refrain; the refrain might add an extra voice part. a song of joy, praise, or emotion. (usually religious in nature)