When your large-breasted friend gets all pissy, moody, and and bitchy when she's mad about something. She may exert an annoying, high-pitched noise that sounds something like "eh!". Because of this, you may have real or imagined fears that she'll whack you unconscious with her gynormous tit. Can also be shortened to simply "TW".
"Did you talk to Sarah today?" "No, because she was majorly tit-whacky."
by Sparkly Smash February 4, 2010
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