mute button
US /ˈmjuːt ˌbʌt.ən/
UK /ˈmjuːt ˌbʌt.ən/

1.
a button or control on an electronic device that silences the audio output or input
:
•
Please hit the mute button on your microphone during the meeting.
•
I accidentally pressed the mute button on the TV remote.