Dimmer (noun)

1. A device used to control the brightness of electric lights.
2. A control used to reduce the intensity of a light.

Origin:

The word dimmer is derived from the verb "dim" which means to reduce the brightness of a light.

Examples:

1. He installed a dimmer switch in the living room to control the brightness of the lights.
2. She adjusted the dimmer to create a softer light.
3. The dimmer switch is used to control the level of light in the room.
4. He replaced the old dimmer with a new one.
5. The dimmer was used to create a romantic ambiance in the room.