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

For communities across Sacramento and California, Diwali — the ancient Hindu Festival of Lights — comes with its joyful tradition of illumination to symbolize good over evil, but this year’s celebration is marked with a shadow of disappointment. — Camila Pedrosa, Sacbee.com, 4 Nov. 2026

Previous versions of this luminous logo relied on the screen backlight to provide the illumination. — Joe Osborne, PC Magazine, 29 Oct. 2026

And retained over 85% of their initial output after 2,000 hours of continuous operation under continuous illumination. — Mrigakshi Dixit, Interesting Engineering, 23 Oct. 2026

Although the moon reaches peak illumination shortly after midnight Eastern Time on October 26, the best viewing opportunity for the moonrise will be Sunday evening, October 25, when the moon appears low on the eastern horizon at dusk. — Michele Laufik, Martha Stewart, 23 Oct. 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