mainswitch
nounUK /ˈmeɪnswɪtʃ/
US /ˈmeɪnswɪtʃ/
The main switch is the big switch that turns all the electricity on or off.
Dad flipped the mainswitch before we left the house.
OTHER MEANINGS
2. A switch that controls the main supply of power to a building or machine.
The electrician checked the mainswitch before starting repairs.
3. The primary control used to start or stop a whole system.
Press the mainswitch to start the factory line.
4. A key device for turning a large electrical circuit on or off.
The mainswitch must be off during maintenance.