chlorine

 
Pronunciation: /ˈklɔːriːn/

noun

[mass noun]
  • the chemical element of atomic number 17, a toxic, irritant, pale green gas. (Symbol: Cl)
  • A member of the halogen group, chlorine occurs in nature mainly as sodium chloride in seawater and salt deposits. The gas was used as a poison gas in the First World War. Chlorine is added to water supplies as a disinfectant

Origin:

early 19th century: named by Sir Humphrey Davy, from Greek khlōros 'green' + -ine4

Spelling help

The beginning of chlorine is spelled ch-.