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3.
boo that means like that doesn't look right..or u didn't something stupid...
For example this kid wore an orange shirt and green pants..my brother would go up to him and be like "boo that man"
by Terence June 17, 2004
 
1.
to show disapproval of a subject in a condescending fashion, often signaled by a roll of the eyes or sour face expression.
She wanted to go to THAT movie?? Boo that!
by J Fair June 17, 2004
 
2.
1)to boo something which is 'boo-worthy'

2)to disagree or to not comply with
1)
kid 1- "what a corny fuck'n joke, boo that, boo this man."
Everybody- "boooooo. . .booo." (chop,chop,chop)

2)

Kid 1- "Dude you shouldn't date that Chinese chick, you might get the SARS."
Kid 2- "Boo that, I've got the yellow fever, I need some China beaver"
by R. Dizzle June 17, 2004