A rarely used screenname, often taken by people who shortly thereafter enter the elite ranks of whatever service or game they have obtained the name in. The name is often mispronounced as "Tissfon," "Taurus", and most commonly: "T-Siphon." The correct way to say the screenname, however, is sy·phon, with the T being silent.
"Hey isn't your gamertag Tsiphon? I just saw one of the top ten players of (insert game here) was a Tsiphon."