In social media, it means “alternate account”, which is basically a 2nd (or 3rd, 4th, 5th, etc.) account that you have. Usually an alt is used less than your main account.

Meaning alternative,,,
Many girls now call themselves alt even tho they r basic
They hopelessly try to be alt by forcing themselves to listen to rock, hippie music
Can be found:
Drinking monster
Applying eyeliner
Watching anime
In thrift stores

1. In music, short for Alternative.

2. In RPG, short for Alternate ID.

3. In MPD, short for alter or persona.

4. In keyboarding, the Alt key, located just to the left of the space bar.

5. In HTML, the alternative text attribute of the img tag.

Alt (short for alternative) is a word that describes people who wish to live differently from others by dressing in their own unique style or listening to a genre of music that is much different from everyone else's because it is apart of who they really are. It has nothing to do with BLM,LGBT,or any of that stuff. Only the stupid e-girls want you to believe that crap.

And Alt is an account that is made by the same user of another account and pretends to be someone different. It is usually made to start drama in communities such as fandom and sometimes reddit. They are usually banned by admins on wikis for causing drama and being mean to other users. When their acc is banned they make another acc. This is quite a hassle for admins and they usually ban the IP Adress for all acc’s in the area the alt maker is are blocked. They usually use hacking to get to make these acc’s or to make it seem like other users made the alt when in reality the blocked user is. They usually make acc’s knowing that they will be blocked just to send an offensive message on another users message wall or in the blog posts. They scam and cause trouble for no reason. They are not liked. Being accused of making an alt is tooken to extreme offence. Famous examples of alt makers are ILR (AKA IloveRumania), TLR (AKA TehLoanRanger), TBB, and formerly IILWP (AKAIminlovewithpolandball)

In MMPORGS like MUDs, a reference to a player's supplementary--thus "alternative"--avatar/character. Not the player's primary character but one used for blowing off steam, avoiding a primary character's responsibilities, or exacting anonymous revenge on a player-character you dislike.

Alt or Alternative is a style of music, but is also an umbrella term to describe Alt Subcultures. The main part of being Alt is your music taste and beliefs. You cant call yourself "Emo" if your just sad and dress in black, you have to listen to Emo music. Some Emo bands are Falling in Reverse, My Chemical Romance and Fall Out Boy. Goth is more than just putting on black lipstick and eyeliner. Goth subculture was created by fans of Gothic Rock. Some Goth Rock bands are The Cure, The Sisters of Mercy and Joy Division. Punk is very important, because it pretty much birthed the other subcultures. Being Punk isn't just jelling your hair into spikes. Punk was created because Punk bands rejected mainstream Rock. Some Punk bands are The Clash, The Sex Pistols and Green Day. Grunge is not wearing chains and wearing black ripped jeans. Grunge is a subculture. NOT a fashion style. Grunge is known as of a hybrid of punk and metal. Some Grunge bands are Nirvana, Alice in Chains, and Soundgarden. Metal is also a big part of the Alt Community. Metals not just loud music, its about individuality and freedom. Some Metal bands are Iron Maiden, Black Sabbath and Slayer. Alt beliefs are a gigantic part of the community. If you don't believe in ACAB, BLM, Fuck ICE and LGBTQ rights YOUR NOT ALT. Alt is not just wearing eyeliner, drinking monsters and wearing chains. It has history. Also if your Indie and only listen to Indie Pop, you not Alt, you have to listen to Indie Rock.

gaming: An alternative character, as opposed to one main character you play in a game. Many online games allow the user to make multiple characters. People that make alts to an extreme are said to be altoholics.

An abreviation for the word "Alternative" meaning the type of music.