A person who watches an opponent's part of the screen in a split screen video game (such as Call Of Duty) to see where they are so they can sneak up and kill them. Usually, it is very simple to see if someone is screen watching.

For example, if you see that someone is standing in one spot for a long time and you then scope with your sniper from across the map and they run away right when you start to aim, this is a sign of a screen watcher.

Another example would be a Matt Cowan. This is when you know your opponent does not have radar and you did not shoot your weapon, so your opponent has no way of knowing where you are. A screen watching opponent would take a peek at your screen and then throw a "random" frag grenade across the map and easily kill you. This is another sign of a screen watcher.
Cacioppo: Tyler! What the fuck! You're such a screen watcher! How did you know I was in that building?!

Tyler: Wow, I didn't screen watch at all. Actually, I went into a random building and saw you there so I knifed you.

Stru: *singing* SCREEEEEEN WAAAATCH!

or

Paulo: Wow, Stru, how did you know I was there?

Stru: I saw you on my radar.

Paulo: But you don't have radar...

Stru: ...oh.
by NotMattStru December 8, 2009
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A person who while participating in a game of Halo looks at his opponents screen to gain unfiar advantage. This is considered an extremelty "gay" tactic by seasoned halo players. When discovered, screen watchers should be promply shot in the head.
"Hey Strode, if you don't stop being a screen watcher, I'll pop a cap in yo ass"
by John Dominy August 17, 2007
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That little cheap ass bitch that watches other peoples' screens just to win a game when your at a friends house.
"Dude your little brother is such a screen watcher when we play halo!"
by ScreenWatched October 5, 2009
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A person who while participating in a split screen game, looks at his opponents screen to gain unfiar advantage. This is considered an extremelty "gay" tactic by seasoned players. When discovered, screen watchers should be promply shot in the head.
Hey Kaity, if you don't stop being a screen watcher, I'll pop a cap in yo ass.
by Dylo to Black Bear August 3, 2011
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A person participating in any act of gaming, while watching the opponents screen to gain the lead as a poor advantage. Usually the person lacks skill and performance in gaming so they have to watch other peoples screens to know where they are at all times.
"Hey Ron? How the hell did you know where i was ?" "Cause i am god, ha ha , just kidding. I was watching your screen". -(me)"You have no skill man, your such a screen watcher"
by toeknee666tiger October 12, 2009
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