Drone
Part of speech: noun
Definition: A male bee or wasp, which does not work but can fertilise the queen. A remotely controlled aircraft. A low-pitched hum or buzz. One who performs menial or tedious work; a drudge. One of the fixed-pitch pipes on a bagpipe. A genre of music similar to that of noise.
Part of speech: verb
Definition: To produce a low-pitched hum or buzz. To speak in a monotone way.
Bourdon
Part of speech: noun
Definition: the burden or bass of a melodythe drone pipe of a bagpipethe lowest-pitched stop of an organthe lowest-pitched of a peal of bellsa bumblebee