Top definition
1. K3U is short hand for I <3 U.
2. I <3 U = I love you, basically.
3. K3U originated from Central California in Late 2002.
Girl geek: "I love you, babe!"
Guy geek: "K3U too hun!"
by M. Lohse October 12, 2005
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Jun 24 Word of the Day
An exclamation made when your friends or family are teasing you to a point where you can't handle it anymore and a hissy fit is in order.

Derived from a YouTube user's famed outburst following Britney's lackluster performance at the 2007 VMA's.
Sarah: 'OMG Susan, I can't believe you are wearing the same skirt as yesterday. Oh, and by the way, EVERYONE knows what you did with Kevin on the weekend. Plus you look a little fat, are you retaining water?'

Susan: 'LEAVE BRITNEY ALONE!'
by Billy Chickenhole September 15, 2007
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2
I Love You => I <3 U => K3U

therefore, the I and the < combine to be a K then come the 3 and the U which become K3U
50: K3U Lloyd.
Lloyd: K3U too fiddy.
by J2TEH OOLIA January 30, 2005
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