12s (12er in German language) are all people, who were born at a date, where the amount of milliseconds of the current system time had 12 digits. That includes people that were born between 1973 and September 2001.

While people older than 12s usually are a bit unfamiliar with the internet, 12s are said to be the coolest people in the virtual world. The younger 13s are notorious for being cringe on the internet.
"You're a 12s? Wow, so cool, I wish I was also one of the 12s!"

"Oh cool, another 12s. I was slowly losing braincells in this mass of 13s.
by schneeeee May 24, 2021
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The Seattle Seahawks' dynamic fan base. Regarded as the unrivaled loudest, proudest, most enthusiastic fans in the history of the NFL.
The 12s were in full force at Super Bowl 48; their crowd noise caused the safety to open the game because the Denver Broncos could not hear the snap count.
by Pooh Harrison February 03, 2014
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A day that is significantly luckier than 11/11/11 that everyone should expect to make their biggest wish on.
12/12/12 is much more lucky than 11/11/11!
by dwightonmac54 November 10, 2011
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The date that comes after 12/11/12. Has no real significance in the way we live our lives.
Person 1: Do you know what the date is!?!?
Person 2: Wednesday?
Person 1: No! It's 12/12/12
Person 2: No, I'm pretty sure it's Wednesday.
by Skitzophrenic December 12, 2012
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Masturbating or ejaculating 12 times in 12 hours.
Dude, last night Bobby was challenged to the 12 in 12 challenge and he accepted! His dick's gonna fall off!!
by Tigs978 December 01, 2009
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The lighting schedule for growing marijuana indoors. 12 hours of sunlight/12 hours of complete/uninterupted darkness.
Just finished the veg cycle, now its time to change from 16/8 to 12/12 in order to determine the sex of my plant.
by amp9041 January 01, 2006
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