fluoresce

verb

fluo·​resce flu̇-ˈres How to pronounce fluoresce (audio)
flȯ-
fluoresced; fluorescing

intransitive verb

: to produce, undergo, or exhibit fluorescence
fluorescer noun

Examples of fluoresce in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
One of the first reports of this feature was a 2019 paper, which found that flying squirrels fluoresce under UV light. — Taylor Nicioli, CNN Money, 29 Oct. 2025 The study also referenced research suggesting scorpion exoskeletons can fluoresce under ultraviolet light and may function as a light-sensing surface. — Hanna Wickes, Kansas City Star, 10 Mar. 2026 The color of a comet's coma often indicates what gases may be fluorescing under solar UV radiation, offering clues to the icy body's composition. — Kenna Hughes-Castleberry, Space.com, 11 Nov. 2025 The result is a range of solid-state materials that fluoresce under UV light and boast easily tunable photoluminescent properties. — Mrigakshi Dixit, Interesting Engineering, 10 Nov. 2025 See All Example Sentences for fluoresce

Word History

Etymology

back-formation from fluorescence

First Known Use

1874, in the meaning defined above

Time Traveler
The first known use of fluoresce was in 1874

Rhymes for fluoresce

See All Rhymes for fluoresce

Browse Nearby Words

fluorene
fluoresce
fluorescein
See all Nearby Words

Cite this Entry

“Fluoresce.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fluoresce. Accessed 7 Jul. 2026.

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Kids Definition

fluoresce

verb
flu·​o·​resce
ˌflu̇(-ə)r-ˈes
fluoresced; fluorescing
: to produce, exhibit, or be exposed to fluorescence

Medical Definition

fluoresce

intransitive verb
flu·​o·​resce ˌflu̇(-ə)r-ˈes How to pronounce fluoresce (audio) flōr- How to pronounce fluoresce (audio) flȯr- How to pronounce fluoresce (audio)
fluoresced; fluorescing
: to produce, undergo, or exhibit fluorescence
fluorescer noun
Last Updated: - Updated example sentences
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