This is said when you agree with something being said, usually a strong negative statement or comment about something else but not always.

its commonly used on online chatting forums and can mainly be found on thecomeupboard.com/forum/ where the word was originally created.

same as: yep, ya, word, hella true, fo sho
example 1
guy 1: dude this class fucking sucks!
guy 2: 12345

example 2
guy 1: check out that ass, id hella tap that
guy 2: 12345
by frrrrrrgt July 15, 2008
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The combination an idiot would have on his luggage.
His luggage combination is 12345.
by jaytk October 06, 2006
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some of the worst passwords and get you hacked instantly
Hey get a password 12345 mug for charle
by NotAexpert March 21, 2021
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Rule 12345:

Otherwise known as a reference and

extension to "Murphy's Law"

Whatever can go bad, will, and whatever can

go worse, will also.
Boy 1: Omg, one of my gf's found out I

was cheating!! >.<

Boy 2: you better be careful, your third

might find out too.... *third girlfriend

walks by inconsequentially, overhearing

conversation* WHAT?!?!?!

Boy 1: Damn you, Rule 12345
by EnelKA April 16, 2009
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