Screenhack 

To sneak a peak at an opponent's screen, when competing in a multi-player, online environment, e.g. Call of Duty, in order to find out where they are so you can go shoot them. Screenhackers are the subject of much finger-pointing and deriding upon discovery.

John: "You're looking at my screen you cheating son of a wh*re"

Fred: "No I didn't, I was just checking my watch"

John: "I so caught you screenhacking!"

Screenhack by Pukezilla January 8, 2011

screenjacker 

A video game player who looks at an opponent's television, monitor, or display to gain information on their whereabouts or game status.

Every time we play Doom, I catch Tim glancing toward my screen. He is such a screenjacker.

screenjacker by Oden Nauticus January 24, 2005

screenfucker 

What angry 13 year-olds yell at each other while playing split-screen Halo.

*boom headshot* How did you know I was there?!!! YOU SCREENFUCKER!!!!!

screenfucker by beach house June 16, 2009

screentalker 

Someone who talks shit or big only behind the screen, while in person they'd use common courtesy and be polite. A person who forgets that others on the internet are real people, and says whatever they want to them without any consideration.

Mary is usually pretty polite in person, but she is a hardcore screentalker on Facebook. You wouldn't believe some of the things she says on there.

They were screentalking, saying things like "kill yourself".

Are you screentalking right now, or are you really this awful?

screentalker by cookie_cake August 2, 2018

Screenhooker

Someone who glances at your side of the screen when playing an FPS (First person shooter) Such as Call of duty, Medal of honor, and Time splitters, Using that advantage against you whenever you go around corners, use special abilities, or other hidden places being revealed, tipping the tide of the game into their own favor.

Joe is a screenhooker, because he had looked at Ethan's screen to snipe him out.

Screenhooker by KodiakWolf January 1, 2010

Screenshocked 

When someone takes your phone and changes the screen photo to a picture of themselves.

1. Dude 1 says "what happened to my phone?" Dude 2 say "looks like you got screenshocked!"
2. Watch, I'm gonna screenshock a picture of me on my moms phone.

Screenshocked by Alexmis May 11, 2013

Screenjack 

while looking at one's computer, the surprise pop-up ad that appears independent of the user's actions. typically, this pop-up ad appears to block out the whole screen, and is difficult to close out.

"I was checking out that new website for shoes, and I got screenjacked with an ad for an online university."

Screenjack by mrs. sucksby May 20, 2009