TURN ON

{v.} 1. To start by turning a knob or handle or working a switch; cause to be on. * /Jack turned on the water./ * /Who turned the lights on?/ 2. {informal} To put forth or succeed with as easily as turning on water. * /She really turns on the charm when that new boy is around./ 3. To attack. * /The lion tamer was afraid the lions would turn on him./ * /After Joe fumbled the ball and lost the big game, his friends turned on him./ 4. {slang} The opposite of turning someone off; to become greatly interested in an idea, person, or undertaking; to arouse the senses pleasantly. * /Mozart's music always turns me on./ 5. Introducing someone to a new experience, or set of values. * /Benjamin turned me on to transcendental meditation, and ever since I've been feeling great!/ Contrast: TURN OFF.