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A slumbie is a slang term for a sleep over. When one person sleeps over another's home.
2x Stuf'd and Vanilla Cracka had an amazing slumbie at 2x's house last night
by 2x Stuf'd February 06, 2009
Verb: the act of slumber partying.
Sarah! Are we going to slumbie saturday night?
by laadygaaga August 09, 2010