Tweakitis Share definition Flag A person who is diagnosed with being a tweaker, or a person who constantly stays up and does random things. look at that girl organizing the towels in aisle three, she must have tweakitis. Tweakitis by thatoneguyoverthereinthestall December 30, 2009 0 0 Get merch Get the Tweakitis mug. Buy Now — $32.95 See more merch