The term domain is a technical term simply used to logically group a bunch of stuff together. In babblevoice speak, under a domain you have a bunch of phones, a bunch of call rules, a bunch of users who have access to manage these items and other stuff. Typically a domain is used to represent a business’s phone system. There is no reason why it might not be used differently though. A business might decide to have several babblevoice domains representing different parts of their business.
In surgery speak, it would probably represent a surgery and maybe a branch surgery. Some organisations group more surgeries together into one domain. The choice is yours.
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