illumination

noun

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

1

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

a

: spiritual or intellectual enlightenment

b(1)

: a lighting up

the illumination of the room

(2)

: decorative lighting or lighting effects

c

: decoration by the art of illuminating

a medieval manuscript with magnificent illumination

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

Synonyms of illumination

• explanation
• interpretation
• illustration

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

Recent Examples on the Web

Too bad Illinoisans will not join in the illuminations at home for our nation’s semiquincentennial — at least not legally. —Brad Weisenstein, Chicago Tribune, 5 Feb. 2026

American Airlines said its pilots receive training on how to handle potential laser illumination incidents and are instructed to report any such events immediately. —Kelly McGreal, FOXNews.com, 3 Feb. 2026

Expressly used for events, the station’s Platform 3 morphed into the Edo-Tokyo Museum, complete with exhibitions, illuminations, food tastings, and the sense that both the Japanese capital’s past and future have always been at home in Ryogoku. —Jonathan Delise, Travel + Leisure, 31 Jan. 2026

The moon is entirely visible at its peak illumination. —Nathaniel Levine, Idaho Statesman, 31 Jan. 2026

Word History

Etymology

Middle English illumynacioun, borrowed from Medieval Latin illūminātiōn-, illūminātiō, going back to Latin, "illustriousness," from illūmināre "to give light to, illuminate entry 1" + -tiōn-, -tiō, suffix of verbal action

First Known Use

14th century, in the meaning defined at sense 1

Rhymes for illumination

• abbreviation
• abomination
• acceleration
• accentuation
• accommodation
• accreditation
• acculturation
• accumulation
• acetylation
• adjudication
• administration
• adulteration

Kids Definition

illumination

noun

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

1

a

: the action of illuminating or state of being illuminated

b

: amount of light

2

: gold or colored decoration in a manuscript

Medical Definition

illumination

noun

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

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

illuminate

il-ˈü-mə-ˌnāt 

transitive verb

illuminated; illuminating