turn upon

Verb

turn on (third-person singular simple present turns on, present participle turning on, simple past and past participle turned on)

1. (transitive) To set a flow of fluid or gas running by rotating a tap or valve.
   • Turn on the tap/faucet.

   Antonyms:

   turn off

2. (transitive) 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.
3. (intransitive) To start operating; to power up, to become on.
   • My computer won't turn on.

   Synonyms:

   turn against

4. (transitive) 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.
5. (transitive) To sexually arouse.
   • John's a maid fetishist. Maid outfits really turn him on.
6. (intransitive, slang) To take drugs.
   • "Well, they seem to always have dope up there, and I like to turn on, too."
     "You do?"
     "Sure. Cops is just people. I don't drink, so I gotta do something to get my kicks."1971, Chuck Barnes, Revenge, Timely Books

See all 12 meanings of turn on