from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. A unit of illumination equal to one lumen per square centimeter.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A photometric unit of illuminance, or luminous flux through an area (symbol ph).
  • v. to photograph

from The Century Dictionary and Cyclopedia

  • n. A proposed photometric unit equal to an illumination of one lux for one second; one lumen of light-flux applied to a surface of one square meter for one second of time.
  • n. Abbreviations of photographic
  • n. [lowercase or cap.] of photography.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. a unit of illumination equal to 1 lumen per square centimeter; 10,000 phots equal 1 lux


Greek phōs, phōt-, light; see bhā-1 in Indo-European roots.
(American Heritage® Dictionary of the English Language, Fourth Edition)
Coined by André Blondel in 1921. See photo-. (Wiktionary)
Shortening of photograph (Wiktionary)



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