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 6, 2018
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Alt/indie girls, or alt people (mostly teenage girls) typically wear thrifted clothes, dyed hair, and fun/unique makeup. “Alt” is not entirely based on appearance, as it can also be about the music you listen to and your political views and opinions. You can have an “alt style” but also not have the personality. If you gatekeep, judge or are just mean in general, you’re not considered (fully) alt. Most people who do this and still say they’re “alt” aren’t alt, they’re just following the trend and seeking validation😁 Alt is short for alternative. Alternative is also a music genre.
Person 1: “I’m an Alt Girl
Person 2: “I’m a skater boy
by toebuttfart September 14, 2020
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Far Right college virgins who have an obsession with 4chan and anime porn. They tend to be anti female either because they can't get any or are gay because they can't get any.
Alt-Rightist 1: fuck these regressive, triggered liberal cucks!
Alt-Rightist 2: Yeah, lets go to our room and watch interracial anime porn with our Make America great again hats!
by STUPID USER NAME August 25, 2016
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Using in online gaming, specifically Warcraft III in one of two ways.

1. A way of tricking a n00b in to quitting the game.
2. A term meant to insult or demean a n00b after you pwn them in a game or chat room.
1. "Takes place in Warcraft III game"

Gosuplayer: I pwn you… I have so much gold I will never run out!
N00bplayer: OMFG I knew you hack!
Gosuplayer: ROFL… yes n00b I hack lol
N00bplayer: I report you for resource hack
Gosuplayer: LOLZZZZZ – Alt qq for free gold
N00bplayer has left the game
Gosuplayer is victorious

2. "Takes place in a Warcraft III chat room"

Player 1: WOW I pwnd you hard
Player 2: stfu you go lucky
Player 1: lol stupid n00b
Player 2: Hack more you hacker jew
Player 1: LMFAO!! Don’t cry n00b
Player 1: gfg fegit - Alt qq life now plz
Player 3: ROFL That noob just go pwnd hard
by mac6433 June 1, 2005
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Being your truest self no matter the environment. A term especially for people of color that are into different fandoms, anime, alt music, clothes, ect, but haven’t felt comfortable expressing fully until now. Creator is Grizz
Welcome to hood alt TikTok, stay for a while and vibe with us
by Splashh July 21, 2020
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When someone says some dumb shit and you use NVIDIA ShadowPlay to record the last couple minutes to roast them.
Skid: I'm gay like lain
God: 'alt f10' that's gay as hell bro
by hunggodakajc February 7, 2018
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online forum user who uses an alternative account; the use of alt-nics have already been been banned in Quake3World.
Aren't you an alt-nic?
by Honushi January 1, 2004
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