No, Xorg (or at least the component of Xorg I think you're thinking about) is the server -- specifically, the display server.
Clients -- the individual applications you run -- connect to the display server to draw themselves. (so, e.g., xeyes, xlogo, Firefox, etc. are the clients).
Clients -- the individual applications you run -- connect to the display server to draw themselves. (so, e.g., xeyes, xlogo, Firefox, etc. are the clients).