Longman Dictionary of Contemporary English homepage

Date: 1800-1900
Language: Modern Latin
Origin: Greek selene 'moon'

selenium

 noun
     
Related topics: Elements
se‧le‧ni‧um [uncountable]
HCE a poisonous chemical substance, used in electrical instruments to make them sensitive to light. It is a chemical element: symbol Se
Definition from the Longman Dictionary of Contemporary English
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