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selenium

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noun se·le·ni·um \sə-ˈlē-nē-əm\

Simple Definition of selenium

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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of selenium

  1. :  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 element table

Origin and Etymology of selenium

New Latin, from Greek selēnē moon, from selas brightness


First Known Use: 1818


SELENIUM Defined for Kids

selenium

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noun se·le·ni·um \sə-ˈlē-nē-əm\

Definition of selenium for Students

  1. :  a gray powdery chemical element used chiefly in electronic devices




Medical Dictionary

selenium

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noun se·le·ni·um \sə-ˈlē-nē-əm\

Medical Definition of selenium

  1. :  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 element table, selenosis




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