standbylight

noun
UK /ˈstændbaɪlaɪt/
US /ˈstændbaɪlaɪt/

A standbylight is a small lamp that stays on in case the main lights go out.

We keep a standbylight in the hallway so we can see during a power cut.


OTHER MEANINGS

2. A light that stays glowing on a device to show it is ready to use.

The little standbylight on the TV glows red when it is off.

3. A soft light left on at night so people can find their way.

She plugged in a standbylight near the stairs for her grandmother.

4. A person or thing that is kept ready to help if needed.

The coach called him the team's standbylight, always ready to play.