Acronym standing for "best friend until death" for people who will be friends until they die. It is an alternative to the hugely overused BFF and it just sounds awesome, so you should say it.
Jenny: Wow, you are soooo awesome!
Dmitri: Really, I am!?
Jenny: Yes. you are definitely my BFF....no...YOU ARE MY BFUD!
by H, C, K, R, & E April 19, 2009
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