You can turn off chat for all of your meetings and webinars from your Profile Settings, if you do not want to use the chat in your meetings and webinars. This will prevent the host, co-hosts, and participants from chatting for any meetings you host. The Chat option will no longer appear in the Meeting Controls.

Or you can disable the Private Chat, which will prevent participants from sending messages to individuals instead of the entire group.

Sign in to the Zoom web portal at https://salisbury.zoom.us
Click Settings.
Click the Chat and Private Chat toggles to disable(grey) in-meeting chat.
Click Save Changes.

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