illuminance

[ ih-loo-muh-nuhns ]

/ ɪˈlu mə nəns /

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noun Optics.

illumination (def. 6).

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Origin of illuminance

First recorded in 1940–45; illumin(ate) + -ance

Words nearby illuminance

ill-timed, ill-treat, illude, illume, illuminable, illuminance, illuminant, illuminate, illuminati, illuminating, illumination

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

British Dictionary definitions for illuminance

illuminance

/ (ɪˈluːmɪnəns) /

noun

the luminous flux incident on unit area of a surface. It is measured in luxSymbol: E v Sometimes called: illumination Compare irradiance

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for illuminance

illuminance

[ ĭ-lōō′mə-nəns ]

The luminous flux per unit area at any point on a surface exposed to incident light. It is measured in luxes. Also called illumination