chlorine

/ˈklɔrin/

/ˈklɔrin/

Other forms: chlorines

Chlorine is a chemical that's commonly used to purify water. That bleach-like smell at the public swimming pool? That's chlorine.

At room temperature, chlorine is a greenish-yellow gas. It was identified as a separate element in 1810 by the British chemist Sir Humphry Davy, who named it after the Greek khlōros, "pale green." Modern uses of chlorine have ranged from a weapon in chemical warfare to public sanitation. Today, most public water is treated with chlorine to kill dangerous bacteria.

Definitions of chlorine

1. noun

   a common nonmetallic element belonging to the halogens; best known as a heavy yellow irritating toxic gas; used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt (as in sea water)
   synonyms: Cl, atomic number 17

   types:

   radiochlorine

   a radioactive isotope of chlorine

   type of:

   chemical element, element

   any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter

   gas

   a fluid in the gaseous state having neither independent shape nor volume and being able to expand indefinitely

   halogen

   any of five related nonmetallic elements (fluorine or chlorine or bromine or iodine or astatine) that are all monovalent and readily form negative ions