But the constant humming drone was sufficient to drown out any other noise.

Then the thuds became a constant drone and the sky exploded in color.

The constant drone in her head made it hard to think.

The roar of the river was a constant drone in his ears, oddly soothing.

The instrument is often used to provide solely a constant drone.

THE constant drone of a computer cooling fan can be annoying.

In warm weather, the constant drone of large fans and air conditioners dominated all other sounds.

The constant drone and mechanism of the church organ fascinated the young boy.

The constant drone of helicopters searching overhead had not helped, either.

Tiny speakers on the floor play the constant drone of white noise.