Definition of illuminant
: an illuminating device or substance
Examples of illuminant in a Sentence
at the time, a spermaceti candle was the brightest indoor illuminant available
Recent Examples of illuminant from the Web
Many others had restrained trade by putting out oil which prejudiced the people against kerosene oil, as it was termed, as an illuminant, because of poor quality and consequent great danger.
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
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