It is an abbreviation which means Bad-Ass-Mother-Fucker-In-The-House which is normally used to state the strength of a person while entering a place, so that other people would know who they are messing with.
1. Yo dude, check out there is a BAMFITH

2. Hey laish look there she is with a BAMFITH

3. BAMFITH!!!!
by ashey101 May 31, 2011
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