verb - the action of someone online who signs into a chatroom and stays inactive for a long period of time so that everyone in the chat believes that person to be away from their keyboard, but as soon as someone says somethign about them or speaks about a topic that they have knowledge about they pop into the conversation. this can either be referring to a good friend or a frequent visitor who is annoying.
person #1, "hey man did you hear about Gilly?"
person #2, "no i didn't, why, whats up?"
Gilly, "did someone just say my name?"
person #1, "goddam it gilly you fuckin invisibated me again you dick!"
Gilly, "LOL -.-"