turn on

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.