It's a combination of letters on your keyboard that you use on your friend to piss them off.
Guy1(on laptop)

Guy2:"clicks alt f4 and deletes the page Guy1 was on"
Guy1:WHAT THE FUCK MAN!?!?!!?
Guy2: ha ha get prank bro you must get of that loli henti.
by Daggermaster9900 December 06, 2018
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A command that can do almost anything, except close a program
Person 1: How do I save my essay?
Person 2: Just press alt+f4
by Ar-Pharazon King of the Sea November 14, 2018
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kweed stands for "kpop" + "weed" due to its highly addictive content
kweed f4 is a cult (group chat) consisting of 4 kweed dealers who are high 24/7
their representative symbol is "ዊ"
they recently realized that they have no friends
a: no matter what group chat we join
a: it's always the four of us talking
b: we have no friends
b: kweed f4
c: why
c: xswl
d: *picture of jyp crying*

5 seconds later:

d: siwhdjkehdjkehjkdhjkewkjdnekndk
d: *video of park jimin*
a: sjkwkd
b: hdekhdjkehd
c: g2edgh2ebdj

b: *video of kim jisoo*
b: i'm hiiigh
a: so that's why we don't have friends
d: *picture of jyp crying and laughing*
c: why
c: xswlll
by nothaydenz August 18, 2020
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Alt F4 is the prank those 9 year-old's follow.

9 year-old playing Fortnite: Hey, do you know a hack to get a Victory Royale and everyone instantly dies
Pro: Yes I do, hold Alt and F4 at the same time and then let go.
9 year-old: (Gets off game, raging, and destroying his keyboard)
Press Alt F4
by ADEEPOCEAN May 21, 2020
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A key combination / panic spell that you must use quickly when you're about to lose or die in a video game (on PC) to escape your inevitable demise. Some MMOs however implement penalties for using this to escape doom however as it is considered cheating.
A: "Yo I was playing Roblox Jailbreak and this cop was about to arrest me so I've alt f4 out."

B: "What, I tried that on League of Legends and I was suspended from playing any servers."

A: "Oh Shi-"
by Kit Rat January 27, 2019
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