phos·​phor ˈfäs-fər How to pronounce phosphor (audio)
variants or less commonly phosphore
: a phosphorescent substance
: a luminescent substance that emits light when excited by radiation (such as electrons) and is used especially in fluorescent lamps and cathode-ray tubes

Example Sentences

Recent Examples on the Web But Elbit’s latest device uses white phosphor instead, producing black and white images, which officers say creates more contrast and greater clarity at night. Washington Post, 24 May 2021 The same works with a laser but, because its light is so intense—1,000 times brighter than an LED—the phosphor filter burns out immediately. The Economist, 4 Jan. 2020 All these games were designed for standard-definition CRTs, where the inherent blur of scanlines and phosphors helped smooth out rough edges. Kyle Orland, Ars Technica, 27 Nov. 2018 The Arcade filter leaves off the scanlines and instead adds a shadow mask effect, simulating the RGB phosphors of an arcade monitor. Aurich Lawson, Ars Technica, 29 May 2018 The devices use an electromagnet to excite a phosphor coating, which creates visible light. Andy Rosen,, 14 Mar. 2018 On top of that purple LED is a collection of metals called a phosphor. Sophia Chen, WIRED, 10 Aug. 2015 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'phosphor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


Latin phosphorus, from Greek phōsphoros, literally, light bringer, from phōsphoros light-bearing, from phōs light + pherein to carry, bring — more at fancy, bear

First Known Use

1706, in the meaning defined at sense 1

Time Traveler
The first known use of phosphor was in 1706

Dictionary Entries Near phosphor

Cite this Entry

“Phosphor.” Dictionary, Merriam-Webster, Accessed 28 Nov. 2022.

Kids Definition



phos·​phor ˈfäs-fər How to pronounce phosphor (audio)
: a substance exhibiting phosphorescence

Medical Definition



variants also phosphore
: a phosphorescent substance
specifically : a substance that emits light when excited by radiation

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