look up any word, like donkey punch:
 
2.
Bold Italicized Underlined: used in reference to the tool bar above word documents. Typically used in text messages when you don’t have such a tool bar available.
Did you see Becky just walked up and kicked Justin in the junk and stuff?

Like N.W.! Why?!

She heard that he skipped the home coming dance the go screw some slut. But he was at like the hospital with his sick Grandpa or something!

He's soooo sweet!

Yeah and Becky is a B.I.U. Bitch!
by Kyle Jordan September 24, 2008
 
1.
BIU
This is the abbreviation meaning beat it up.
Neil: What did you do last night, BIU?
Paden: yeah i took that girl home and BIU like a nigga.
by Arni Duckhart December 31, 2009