MCSing is Multiple Cyber Socialising, which is the term given to the situation when a person is in conversation with various people through different forms of communication. This includes internet chat rooms, social networks, phone communication, and basically anything that involves a means of communication such as internet or phone networks.
Man 1: "Hey man, what you up to?"
Man 2: "Oh just MCSing, the usual."
Woman 1: "How will I be able to finish all this work?"
Woman 2: "Stop MCSing you fool!"
Man 2: "Oh just MCSing, the usual."
Woman 1: "How will I be able to finish all this work?"
Woman 2: "Stop MCSing you fool!"
by The Testosterone Bullet October 14, 2009