onoff

2. A setting or control that has only two positions, on and off.

Turn the dial to the onoff position before you start the machine.

3. A pattern of quickly starting and stopping again and again.

The flickering bulb made an onoff flashing in the dark room.

4. A simple way to describe something that keeps changing between two states.

His mood was onoff all day, happy one minute and grumpy the next.