look up any word, like cleveland steamer:
 
1.
acronym. back that ass up. often said in crowded clubs. or in public places that call for a little grinding. betches love acronyms.
Last week at the club I was dancing with Tyler. We never spoke a word to each other, except he did shout btau which i took more than literally.

Laura queens the btau. She drops that shit like you wouldnt believe.
by tjttsutmanhtattansutsutsut April 06, 2011