buzzer
nounUK /ˈbʌz.ər/
US /ˈbʌz.ɚ/
A buzzer is a little thing that makes a loud buzzing sound.
The buzzer rang when the cookies were ready.
OTHER MEANINGS
2. A device that makes a buzzing sound to get someone's attention or warn them.
Press the buzzer so the nurse knows you are here.
3. A game show or quiz device that players press to answer first.
She hit the buzzer before anyone else knew the answer.
4. An electronic device that makes a humming or vibrating sound.
The old fridge buzzer kept us awake all night.