Server to server = Server client to server?

For a server to server connection, is the connecting server considered as a client of the accepting server or is it not?

I have the following classes:

Connection             <--- base class of the following two
ClientConnection       <--- client
ServerConnection       <--- server
ServerClientConnection <--- server as a client of another server.

But then I came across something that states "A client is anything connected to a server that is not another client".

Comments please...


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