il·​lu·​mi·​nant | \ i-ˈlü-mə-nənt How to pronounce illuminant (audio) \

Definition of illuminant

: an illuminating device or substance

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Synonyms for illuminant


beacon, lamp, light

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Examples of illuminant in a Sentence

at the time, a spermaceti candle was the brightest indoor illuminant available

Recent Examples on the Web

Distilling rock oil produced multiple interesting compounds, one of which looked like an ideal illuminant. Charles R. Morris, WSJ, "‘Energy’ Review: The Path to Power," 21 June 2018

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

First Known Use of illuminant

1644, in the meaning defined above

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Time Traveler for illuminant

The first known use of illuminant was in 1644

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More Definitions for illuminant


il·​lu·​mi·​nant | \ -nənt How to pronounce illuminant (audio) \

Medical Definition of illuminant

: an illuminating device or substance (as for a microscope)

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Comments on illuminant

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


recurring in steady succession

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