il·​lu·​mi·​na·​tion | \i-ˌlü-mə-ˈnā-shən \

Definition of illumination 

1 : the action of illuminating or state of being illuminated: such as

a : spiritual or intellectual enlightenment

b(1) : a lighting up

(2) : decorative lighting or lighting effects

c : decoration by the art of illuminating

2 : the luminous flux per unit area on an intercepting surface at any given point

3 : one of the decorative features used in the art of illuminating or in decorative lighting

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Examples of illumination in a Sentence

When taking photographs indoors, use a flash for illumination. They traveled to the temple in search of spiritual illumination. an old manuscript with beautiful illuminations
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Recent Examples on the Web

The Eiffel tower during Christmas illuminations on November 22, 2017 in Paris, France. Nina Sovich, WSJ, "Europe in Winter: 35 Reasons to Visit Off-Season," 21 Nov. 2018 That near disaster didn’t prevent Westinghouse from running his own experiment on gas illumination by erecting a 60-foot-tall pipe on his property and lighting off the gas plume. Popular Mechanics Editors, Popular Mechanics, "In Defense of Elon Musk," 16 Oct. 2018 Nvidia has been loudly trumpeting its interest in global illumination lighting systems and on delivering hardware that can make this rendering pipeline far more efficient ever since a major reveal at this year's Game Developers Conference. Sam Machkovech, Ars Technica, "Nvidia’s new RTX 2080, 2080 Ti video cards ship on Sept. 20, starting at $699," 20 Aug. 2018 Real-time ray tracing mimics how light behaves in the real world by mapping out rays that originate from 3D illumination sources in a scene. Brad Chacos, PCWorld, "RTX on! Battlefield V becomes the first game to support DXR real-time ray tracing," 14 Nov. 2018 The illumination satellite will be eight times as bright as the actual moon and may even replace the city’s streetlights. Stavros Agorakis, Vox, "Vox Sentences: A mysterious, paralyzing disease hits the US," 18 Oct. 2018 But, unlike a normal full moon that reflects the sun’s illumination, during a lunar eclipse, the moon emanates the Earth’s shadow (known as the umbra). Aliza Kelly Faragher, Allure, "A Beginner's Guide to Eclipses in 2018 and How They Can Affect Your Life," 16 July 2018 No operator's license; no valid driver for temps; Miles Road: A Solon woman, 20, was initially stopped for no rear license plate illumination on the night of May 2. Thomas Jewell,, "One suspended license, and one temps: Bentleyville police blotter," 4 May 2018 And when the sun starts to set, a few cars' headlights in a nearby parking lot provide illumination, since the airport features no artificial light. Amanda Greene, Woman's Day, "10 Terrifying Airport Runways," 27 Apr. 2011

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'illumination.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of illumination

14th century, in the meaning defined at sense 1

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Statistics for illumination

Last Updated

8 Dec 2018

Look-up Popularity

Time Traveler for illumination

The first known use of illumination was in the 14th century

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More Definitions for illumination



English Language Learners Definition of illumination

: light that comes into a room, that shines on something, etc.

: knowledge or understanding

: a gold or colored decoration in an old book


il·​lu·​mi·​na·​tion | \i-ˌlü-mə-ˈnā-shən \

Kids Definition of illumination

: the action of lighting something : the state of being lighted


il·​lu·​mi·​na·​tion | \il-ˌü-mə-ˈnā-shən \

Medical Definition of illumination 

1 : the action of supplying or brightening with light or the resulting state

2 : the luminous flux per unit area on an intercepting surface at any given point

called also illuminance

Other Words from illumination

illuminate \il-​ˈü-​mə-​ˌnāt \ transitive verb illuminated; illuminating

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Comments on illumination

What made you want to look up illumination? Please tell us where you read or heard it (including the quote, if possible).


to enclose within walls

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