The focused beam of light in the above photo shines in various directions due to the photographer’s long exposures. Photo by Maximilian Orlowsky on Pexels.com

Definition

Noun

  • A beam of light from a buoy or lighthouse that’s been concentrated by prisms or lenses.

Origin

18th century. From the Greek word, dioprikos, meaning roughly refraction.

Comments

See also Fresnel lens.

References

Rogers, J.G. (1985). Origins of Sea Terms. Mystic Seaport.