look up any word, like b4nny:
 
1.
MBFF; The definition? Mexican Best Friend Forever;
Can also be defined: My Best Friend Forever.
You're my MBFF!
by McKenzie Ducky October 15, 2012
 
2.
my best friend forever
Sally is my mbff...
Sally is mbff...
by shannonrb64 October 27, 2007