Common typo among people who like to insert many exclamation points to the end of a sentence, caused by accidentally releasing the Shift key before the 1 key, and sending the message without previewing it to realize the typo had been made.

Often used on purpose to make fun of such accidents and the people who make them, or as part of leetspeak.

A similar but less-joked-about occurrence is the tendency to insert backslashes after a string of question marks.
I DON'T BELIEVE IT!!!!!!!!!!11111

ARE YOU JOKING????????///
by CtrlAltDestroy August 17, 2005
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Punctuation commonly used in l33tspeak that emerged from a typo.
*** rul0r killed Player with a headshot from m4a1 ***
*** rul0r killed (1)Player with a headshot from m4a1 ***
*** rul0r killed (2)Player with a headshot from m4a1 ***
*** rul0r killed (3)Player with a headshot from m4a1 ***

Player: omg taht d00d h4x0rz!!!!111
by chs February 19, 2004
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When you copy and paste "!1!1!1!1!1!1!1!1!1!1" and go too far.
Person 1: SO FUNNY!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1!1

Person 2: Did this guy get crazy with the paste button?
by January 1, 2018
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used at the end of an extremely sarastic statement
i absolutely love my life!1!1!1!1
im so pretty omg!1!1!1!1
by helpfulgal01 June 10, 2017
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Used to make a sarcastic statement even more exaggerated.
Jacob Sartorius is my one true love!1!1!1!
McDonalds is such a healthy place to eat!1!1!1!
by zai.g0ddess August 20, 2016
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Something that you out at the end of your sentence to be sarcastic
Nice shoes!1!1!1!1!
by ilovemarcushxoxo December 2, 2016
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the repeated usage of 1!!11! indicates the sarcasm after a phrase, sentence, or word.
for example
-" i hate you for saying that!1!1!1"
-" i hate you for saying that!1!1!1"
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