se·​le·​ni·​um | \ sə-ˈlē-nē-əm How to pronounce selenium (audio) \

Definition of selenium

: a photosensitive element that occurs in both crystalline and amorphous forms, is obtained chiefly as a by-product in copper refining, and is used especially in glass, semiconductor devices, and alloys — see Chemical Elements Table

Examples of selenium in a Sentence

Recent Examples on the Web

Late-Night Spa: Wi Spa View this post on Instagram With the help of thousand-year-old minerals such as calcium, magnesium, iron, sodium and selenium, our salt sauna improves the physical, chemical and hydrodynamic conditions of the body. Taylore Glynn, Marie Claire, "The Must-Visit Spas & Salons in Los Angeles," 6 Sep. 2019 The teen also had a B12 and vitamin D deficiency, low amounts of copper and selenium in his blood, high zinc and low bone density. Julie Mazziotta,, "Teen Boy Developed Blindness from Junk Food Diet, Study Says," 4 Sep. 2019 The selenium isotopes were detected using a method that took samples from mantle rocks, previously brought to the surface from plate tectonic processes and measured. Fox News, "Meteorite strikes made life on Earth possible, study says," 14 Aug. 2019 The leaders want state and federal officials to fund better long-term water quality monitoring and to adopt a strict water quality standard for selenium. USA TODAY, "Big butter sculpture, sweet guitar, owl released: News from around our 50 states," 24 July 2019 Years in the future this would create a toxic environment for many animals, exceeding chronic exposure standards for cadmium, copper, zinc, and selenium, the EIS notes. Douglas Main, National Geographic, "In a land of wild cats and scarce water, a battle over mining heats up," 25 Apr. 2019 Coal ash can contain potentially harmful substances such as arsenic, lead, cobalt, and selenium. Dennis Pillion |,, "Alabama Power sticks to plan to cover coal ash ponds, despite concerns," 12 July 2019 Multivitamins and other supplements — including selenium, vitamin A, vitamin B6, vitamin C, vitamin E, vitamin D alone, calcium alone, folic acid and iron — did not have a significant effect on death or heart disease, according to the study. Steven Reinberg,, "More evidence supplements won’t help the heart," 11 July 2019 Lab meats can have the beneficial nutrients of meat—iron, vitamin B12, selenium, niacin, and so forth—while also cutting down on the bad stuff, namely the cholesterol and fat content, by integrating only as much as is needed for flavor. Amanda Little, The New Republic, "The Meat Mogul’s Case For Lab-Grown Beef," 1 July 2019

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

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First Known Use of selenium

1818, in the meaning defined above

History and Etymology for selenium

New Latin, from Greek selēnē moon, from selas brightness

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Statistics for selenium

Last Updated

18 Sep 2019

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Time Traveler for selenium

The first known use of selenium was in 1818

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English Language Learners Definition of selenium

technical : a chemical element that is used in electronic devices to make them sensitive to light


se·​le·​ni·​um | \ sə-ˈlē-nē-əm How to pronounce selenium (audio) \

Kids Definition of selenium

: a gray powdery chemical element used chiefly in electronic devices


se·​le·​ni·​um | \ sə-ˈlē-nē-əm How to pronounce selenium (audio) \

Medical Definition of selenium

: a nonmetallic photosensitive element that occurs in both crystalline and amorphous forms, is an essential trace element found especially in grains and meat, and is used chiefly in glass, semiconductor devices, and alloys symbol Se — see Chemical Elements Table, selenosis

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More from Merriam-Webster on selenium

Rhyming Dictionary: Words that rhyme with selenium

Spanish Central: Translation of selenium

Nglish: Translation of selenium for Spanish Speakers Encyclopedia article about selenium

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to wander slowly or to speak indistinctly

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