drone
drone / drōn/ • v. [intr.] make a continuous low humming sound: in the far distance a machine droned. ∎ speak tediously in a dull monotonous tone: he reached for another beer while Jim droned on. ∎ move with a continuous humming sound: traffic droned up and down the street.• n. 1. a low continuous humming sound: he nodded off to the drone of the car engine. ∎ inf. a monotonous speech: only twenty minutes of the hour-long drone had passed. ∎ a continuous musical note, typically of low pitch. ∎ a musical instrument, or part of one, sounding such a continuous note, in particular (also drone pipe) a pipe in a bagpipe or (also drone string) a string in an instrument such as a hurdy-gurdy or a sitar.2. a male bee in a colony of social bees, which does no work but can fertilize a queen. ∎ fig. a person who does no useful work and lives off others.3. a remote-controlled pilotless aircraft or missile.