1. Shorthand for Fusion.
2. One who pwns others.
WHITE GUY: "fusi sucks"
FUSI: Shut up or I'll kill you.
WHITE GUY: "fusi sucks!!"
FUSI: *kills white guy*
WHITE GUY: *bleeding*
FUSI: "Thank you."

Narrator: In this example, we clearly see the 'fusi' 'pwnt' the white guy.
by t3h gEno April 30, 2005
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FUSI is a acronym for FUn, Sexy, In control. FUSI is a slogan for the new sexy clothing company SplitPeaches.com
Live the Split Peaches FUSIgirl lifestyle. Be FUn, Sexy, In control!!
by SplitPeaches.com March 15, 2009
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