Mute
From neox4t wiki
(MUTE) - Moderators and above can ban silently
Mute allows moderators and above to ban a user without them knowing. Guests in the chat will not be able to see the ban message, whereas members and above will.
To mute a user, click on their name, click "Ban", and press the "Mute" button. The maximum amount of time that you can mute a user is 1 hour.
Note: You must be a moderator to use this power. However, similar to the ban duration, GControl allows you to customize which ranks are allowed to mute.