BURDEN (3)

Bur″den (bûr″d'n), n. [[OE. burdoun the bass in music, F. bourdon; cf. LL. burdo drone, a long organ pipe, a staff, a mule. Prob. of imitative origin. Cf. Bourdon.]] 1. 1. The verse repeated in a song, or the return of the theme at the end of each stanza; the chorus; refrain. Hence: That which is often repeated or which is dwelt upon; the main topic; as, the burden of a prayer.
I would sing my song without a burden. Shak. 2. 2. The drone of a bagpipe. Ruddiman.