turn off (something)

When a machine or electronic device is on, you can "turn it off".

"Turn off" refers just to the action of switching something from "on" to "off". After you turn something off, you say that it "is off":

A: Hey, turn off your phone.

B: It's off.

You can also say "shut off", which has the same meaning but is a little more casual.

This phrase appears in these lessons: