turn on phrasal verb ( see also ↑ turn )
1 . turn something ↔ on to make a machine or piece of electrical equipment such as a television, engine, light etc start operating by pushing a button, turning a key etc SYN switch on OPP turn off :
Jake turned on his computer and checked his mail.
2 . turn something ↔ on to make the supply of water, gas etc start flowing from something by turning a handle OPP turn off :
He turned on the gas and lit the stove.
‘I’m thirsty,’ she said, turning on the tap.
3 . turn on somebody also turn upon somebody to suddenly attack someone, using physical violence or unpleasant words:
Peter turned on Rae and screamed, ‘Get out of my sight!’
4 . turn on something also turn upon something if a situation, event, argument etc turns on a particular thing or idea, it depends on that thing:
As usual, everything turned on how much money was available.
5 . turn somebody on to make someone feel sexually excited:
The way he looked at her really turned her on.
⇨ ↑ turn-on
6 . turn somebody on to interest someone, or to make someone become interested in something:
Science fiction just doesn’t turn me on.
turn somebody on to
It was Walter who turned me on to vegetarian food.
7 . turn on the charm also turn it on to suddenly start to be very nice, amusing, and interesting, especially in a way that is not sincere:
Simon was good at turning on the charm at parties.