a low continuous humming sound.
he nodded off to the drone of the car engine
a male bee in a colony of social bees, which does no work but can fertilize a queen.
According to scientific descriptions, a honeybee colony consists of one queen, several thousand worker bees, and at certain times of the year, a few to several thousand drones , or male bees.
a remote-controlled pilotless aircraft or missile.
The EU lacks heavy-lift aircraft, attack helicopters, fighter/ground attack aircraft, and unmanned drones , and has to rely on American spy satellites for basic intelligence.