/kən-ˈtrōl es/
vi. "Stop talking for a second." From the ASCII XOFF character (this is also pronounced XOFF /X-of/). Control-S differs from Control-O in that the person is asked to stop talking (perhaps because you are on the phone) but will be allowed to continue when you're ready to listen to him -- as opposed to Control-O, which has more of the meaning of "Shut up." Considered silly.