selenium

noun se·le·ni·um \ sə-ˈlē-nē-əm \

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

Recent Examples of selenium from the Web

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Origin and Etymology of selenium

New Latin, from Greek selēnē moon, from selas brightness


SELENIUM Defined for English Language Learners

selenium

noun

Definition of selenium for English Language Learners

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


SELENIUM Defined for Kids

selenium

noun se·le·ni·um \ sə-ˈlē-nē-əm \

Definition of selenium for Students

:a gray powdery chemical element used chiefly in electronic devices

Medical Dictionary

selenium

noun se·le·ni·um \ sə-ˈlē-nē-əm \

medical Definition of selenium

:a nonmetallic photosensitive element that occurs in both crystalline and amorphous forms, is an essential trace element found esp. 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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