It usually expresses extreme happiness or anger about something, and a regular exclamation point isn't enough to express how the person feels.
Occasionally the word shift is left out and just the number 1 is used.
Type your email address below to get our free Urban Word of the Day every morning!
Emails are sent from email@example.com. We'll never spam you.
Log in with Facebook to save your favorite definitions
and share them with friends.