v. 1 a tr. cause (a cloud, vapour, fear, darkness, etc.) to disappear or disperse. b intr. disperse, scatter, disappear. 2 intr. & tr. break up; bring or come to nothing. 3 tr. squander or fritter away (money, energy, etc.). 4 intr. (as dissipated adj.) given to dissipation, dissolute. dissipater n. dissipative adj. dissipator n.
[ L dissipare dissipat- (as DIS-, sipare (unrecorded) throw) ]