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

ScreenJack 

To look at another players screen when comencing in gameplay, to benifit the cheating dink.
Most commonly used by men with small penis.
Side effects my include: increased hair groth on penis, facial deformity and loss of penis and/or penise(s).
WARNING
screenjacking is contageous and will spread quicly through your enviroment, if you come across a screenjacker IMEDIATLY close your eyes and masturbate for the best.
An Example is below.

B-Dup: real swell man, i go an energy sword.
Screenjackest4life: i no, im gay.
B-Dup: FUKEN Screen jack to the max
Screenjackest4life: ill screen, then possably jack ur mom.
B-Dup: not if i do first, lil' bitch.

ScreenJack by Ghettonomus January 27, 2008

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

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

Screenlicker 

Someone whose tongue is sticking out on their picture or icon on your phone. Every time they message you, it looks like they are licking your screen. Not to be confused with the below average and desperate window licker. A screen licker is a whole 'nuther level of licking!

When he messaged me, it looked like he was licking my screen.... he is such a screenlicker ;)

Screenlicker by SCREENLICKER February 12, 2015