fluoresce
/fləˈɹɛs/verb
fluoresce is a verb meaning “To emit electromagnetic radiation, especially visible light, when absorbing radiation of some other wavelength” (English Wiktionary, September 2026). It is spelled F-L-U-O-R-E-S-C-E and has 2 syllables, and it appears about once in every 14 million words in written English (wordfreq, 2021 data).
What does fluoresce mean?
verb
- 1
To emit electromagnetic radiation, especially visible light, when absorbing radiation of some other wavelength.
- 2
To cause to fluoresce; to make fluorescent.
- 3
Of colours, to be very bright; to be so bright as to appear to radiate as a light source.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
How do you pronounce fluoresce?
- /fləˈɹɛs/
- /flʊəˈɹɛs/
- /flɔˈɹɛs/
Fluoresce has 2 syllables (counted from its American pronunciation in the CMU Pronouncing Dictionary).
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Recordings: LL-Q1860_(eng)-Vealhurl-fluoresce.wav, Wikimedia Commons (author and licence on each file's page).
Forms of fluoresce
- fluoresces present, singular, he/she/it
- fluorescing participle, present
- fluoresced participle, past
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
How common is fluoresce?
Fluoresce appears about once in every 14 million words in written English, the 114,361st most frequent word form in the list.
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
Fluoresce in Spanish, French, German and Portuguese
In the sense to emit light:
| Language | Words |
|---|---|
| German | fluoreszieren |
| Portuguese | fluorescer |
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Translations are Wiktionary's, by sense; a linked word has its own PlainSpell page.