whirring

Launched more than 30 years ago, AOL dial-up was known for its chirpy whirring start-up sound, but it has long since been replaced by faster alternatives.

We could hear the whirring of the propellers before we could see the drone - barely visible as it sliced through the sky.

While cash might not be as popular as it once was, the opportunity to fashion the next series of banknotes has got brains whirring and tails wagging.

Upstairs was a room filled with PCs, whirring away, buying and selling tickets.

At one point, the besieged Waymos began honking their horns in coordinated cacophony, punctuated by the chants of protesters and the whirring of police helicopters overhead.