オン (on) means “on” | MotiTan Japanese Dictionary

More examples

会議が始まる前に、部屋の照明をオンにします。kai gi ga haji ma ru mae ni heya no shō mei o o n ni shi ma su

I turn on the lights in the room before the meeting starts.

Marks the transition from a device being inactive to being powered and in operation.

機器などを使用できる作動状態にすること、またはその状態。ki ki na do o shi yō de ki ru sa dō jō tai ni su ru ko to ma ta wa so no jō tai

オン (on, "on") comes from English on and was adopted in Japanese to name the act of switching a device on and the resulting state.

The word on is useful in simple Japanese requests about operating electronics, such as asking someone to switch on a television.