phototherapy

noun

pho·​to·​ther·​a·​py ˌfō-tō-ˈther-ə-pē How to pronounce phototherapy (audio)
: light therapy

Examples of phototherapy 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.
There’s also a wood-and-glass sauna, steam room and a hydrotherapy pool with phototherapy—all featuring signature city views. — Caroline Tell, Forbes.com, 14 July 2025 Within a week, Luka showed signs of jaundice, and even phototherapy under blue lights didn't improve his condition. — Alyce Collins, MSNBC Newsweek, 7 Sep. 2025 Innovative hair loss solutions such as advanced laser phototherapy treatments have been shown to reverse hair thinning and promote natural hair regrowth. — Nia Bowers, USA Today, 17 June 2025 One study found ultraviolet-B (UVB) phototherapy to be a safe and effective treatment. — Sarah Bradley, Health, 23 Mar. 2025 See All Example Sentences for phototherapy

Word History

First Known Use

1899, in the meaning defined above

Time Traveler
The first known use of phototherapy was in 1899

Rhymes for phototherapy

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Browse Nearby Words

phototherapeutics
phototherapy
photothermal
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Cite this Entry

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

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Medical Definition

phototherapy

noun
pho·​to·​ther·​a·​py -ˈther-ə-pē How to pronounce phototherapy (audio)
plural phototherapies
: the application of light for therapeutic purposes

More from Merriam-Webster on phototherapy

Britannica.com: Encyclopedia article about phototherapy

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