reflector

noun

1. a person or thing that reflects.
2. a body, surface, or device that reflects light, heat, sound, or the like.
3. reflecting telescope.
4. a substance, as graphite or heavy water, used to prevent the escape of neutrons from the core of a nuclear reactor.

noun

1. a person or thing that reflects
2. a surface or object that reflects light, sound, heat, etc
3. a small translucent red disc, strip, etc, with a reflecting backing on the rear of a road vehicle, which reflects the light of the headlights of a following vehicle
4. another name for reflecting telescope
5. part of an aerial placed so as to increase the forward radiation of the radiator and decrease the backward radiation

n.

also reflecter, 1660s, agent noun in Latin form from reflect. As an attachment to a vehicle, etc., from 1909. As a type of telescope, 1767.

n.

1. A surface that reflects light, heat, or sound.