noun

1. anything that is carried; load
2. anything one has to bear or put up with; heavy load, as of work, duty, responsibility, or sorrow
3. the carrying of loads a beast of burden
4. the carrying capacity of a ship

Etymology: ME birthen < OE byrthen, akin to ON byrthr, a load: for IE base see bear

transitive verb

noun

1. Archaic a bass accompaniment in music
2. a chorus or refrain of a song
3. the drone of a bagpipe
4. a repeated, central idea; theme the burden of a speech

Etymology: ME burdoun, bass in music, refrain < OFr bourdon, a humming, buzzing < ML burdo, wind instrument, bumblebee; of echoic orig.