Reflector (noun)

1. A surface that reflects light, heat, or sound.
2. A device that reflects radio or light waves back to their source.

Origin:

From latin reflectere ("to bend back, turn back"), from re- + flectere ("to ben.d")

Examples:

1. The reflector on the bicycle helped the rider be seen in the dark.
2. A reflector in a car's headlights improves visibility during nighttime driving.
3. The reflector in a torch helps to direct the light in a specific direction.
4. The reflector on a satellite dish helps to receive signals from the satellite.
5. The reflector in a studio helps to control the amount of light used in a photo shoot.