Definition of "turn on" in English

Verb

To set a flow of fluid or gas running by rotating a tap or valve. .mw-parser-output .defdate{font-size:smaller}
- Turn on the tap/faucet.
To power up, to put into operation, to start, to activate (an appliance, light, mechanism, functionality etc.).
- Please turn the lights on so I can see what I'm reading.
- Please turn on automatic updates.
- He'll turn on the charm if he thinks he's losing the sale.
To start operating; to power up, to become on.
- My computer won't turn on.
To introduce (someone to something), and especially to fill them with enthusiasm (about it); to intoxicate, give pleasure to ( + to an object of interest or excitement).
- Attractive packaging can turn buyers on to a product.
- Attractive showroom models can turn buyers on.
- Hearing that song turned me on to jazz fusion.
To sexually arouse.
- John's a maid fetishist. Maid outfits really turn him on.
To take drugs.
To cause to take up drugs, especially hallucinogens.
To aim at.
- He turned the searchlight on the passing planes.
- Cornered by the authorities, the shooter turned the gun on himself.
To rebel against; to suddenly attack.
- Suddenly all his friends turned on him.
To cause (someone) to rebel against or suddenly attack (someone else).
To depend upon; to pivot around, to have as a central subject.
- The argument turned on the question of whether or not jobs would be lost.