After you shut off an electrical or mechanical device, it is shut off. Turned off and switched off are similar to shut off.

1. To block off the passage through; SYN. block off, close off.
2. To isolate or separate; SYN. close off.
3. To stem the flow of; SYN. close off.

When you shut off an electrical or mechanical device, you cut the power going to it so that it stops operating. Turn off and switch off are similar to shut off.