A long body of water curling into an arched form and breaking on the shore. A gesture or signal made by moving one's hand to and fro. A slightly curling lock of hair. A periodic disturbance of the particles of a substance that may be propagated without net movement of the particles, such as in the passage of undulating motion, heat, or sound. Move one's hand to and fro in greeting or as a signal. Style (hair) so that it curls slightly.