to scatter completely; to disperse and cause to disappear; -- used esp. of the dispersion of things that can never again be collected or restored.-to destroy by wasteful extravagance or lavish use; to squander.-to separate into parts and disappear; to waste away; to scatter; to disperse; to vanish; as, a fog or cloud gradually dissipates before the rays or heat of the sun; the heat of a body dissipates.-to be extravagant, wasteful, or dissolute in the pursuit of pleasure; to engage in dissipation.