Means "Fuck yo bitch" The act of stealing a man's girlfriend/wife/person they're talking to and fucking, not neccessarily in that order.
"Damn did you heard what happened to Chris Green?"
-Dude 1

"Naw, what happened?"
-Dude 2

"Cam and T-Sqz FYB'd him with his top two females on his team."
-Dude 1

"Damn, haha."
Dude 2
by That Guy and his friend October 22, 2010
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Fuck Yeah Bitch! An expression used when something is really exciting, or awesome.
"I'm so glad it's Friday, I'm going to get so drunk tonight"

"FYB!"
by mjs82 October 10, 2008
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"Uncuff ya chick brah, its FYB"

"Yo bitch is choosin, jez FYB!!"
by b r e e e e z y July 27, 2009
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Fill Your Boots - inviting someone to go ahead and do something
"Do you mind if I eat the last of the cake?"

"FYB, man."
by Ninjafingerofdoom February 24, 2013
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An acronym representing the phrase "Fine Young Bitch" or "Fine Young Bitches", although the latter is often represented by the plural form of the acronym: FYBs.
Harold: Fo sho, I'm so ready to meet some FYB and show her my dick!"
Mrs. Allen: What does that stand for son?
Harold: Um, fine young...nice lady.
by Tigeriffic January 20, 2014
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Fuck Yeah Boys!

used to define an extremly happy moment.
DJ Luna is coming to town, FYB!
by HAKS August 04, 2005
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Fiddle Your Bean: The act having someone fondle or caress your
intimate lady bits.
"Hey Beth, did Rob FYB last night?"

"Nica, I heard two different guys FYB on two different nights on
your big NYC trip...starting off the new year right!!"
by Milkalicious January 09, 2009
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