irradiance

[ih-rey-dee-uh ns]

noun Physics.

incident flux of radiant energy per unit area.

Also irradiation.

Origin of irradiance

First recorded in 1660–70; ir-¹ + radiance

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for irradiance

Historical Examples of irradiance

Their irradiance was greenish, like the walls; but I was certain that these corpuscles did not come from them.
The Metal Monster
A. Merritt
The irradiance, almost as strong as daylight, but radically different, softened all surrounding objects.
Ben Blair
Will Lillibridge

British Dictionary definitions for irradiance

irradiance

noun

the radiant flux incident on unit area of a surface. It is measured in watts per square metreSymbol: E e Also called: irradiation Compare illuminance

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

Word Origin and History for irradiance

adj.

1660s, from irradiant (1520s), from Latin irradiantem (nominative irradians), present participle of irradiare (see irradiate). Related: Irradiancy (1640s).