light therapy

noun

: the treatment of medical or psychiatric conditions (such as seasonal affective disorder) by the controlled application of light

called also light treatment, phototherapy

Examples of light therapy 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.
Does the seasonal pattern of my mood, energy, and sleep suggest that a treatment such as bright-light therapy might be worth considering? — Tom Gavin, EverydayHealth.com, 21 Oct. 2026 Moore uses the in-office light therapy OptiLight, Andrews uses the prescription drop Miebo, Bowen and Jeong use the anti-inflammatory drop Xiidra, and Aniston started therapy prompted by the drugmaker Shire. — Samantha Agate, Charlotte Observer, 19 Oct. 2026 The Mini Glow Pro is compact and portable, combining red and blue light therapy, therapeutic warming and ultrasonic waves to support youthful, radiant-looking skin. — ABC News, 3 Oct. 2026 Your scalp health, on the other hand, begins via HigherDose’s Red Light Hat, which uses powerful light therapy to support circulation and stronger-looking hair over time. — Valeriya Chupinina, Vogue, 17 Sep. 2026 See All Example Sentences for light therapy

Word History

First Known Use

1987, in the meaning defined above

Time Traveler
The first known use of light therapy was in 1987

Rhymes for light therapy

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Browse Nearby Words

light table
light therapy
light the way
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Cite this Entry

“Light therapy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/light%20therapy. Accessed 27 Oct. 2026.

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Medical Definition

light therapy

noun
: phototherapy
especially : the use of strong light (as of 10,000 lux intensity) for the treatment of depression and gloom (as in seasonal affective disorder)

called also light treatment

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