means to lose concentration and stop being interested in it, e.g. if you’re reading a boring book you might turn off... We also say ‘turn off’ for TVs, lights, radios etc
Please turn off the music. It's too loud.
There's nothing on. Shall I turn off the TV?
Can we turn off the cameras
I wish people would turn off their mobiles in the cinema.
Please turn off your computer
We always turn off the water and electricity at home before we go on holiday.
turn off the tap
Don't forget to turn off the TV before you leave the house.