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chlorine

[ klawr-een, -in, klohr- ]
/ ˈklɔr in, -ɪn, ˈkloʊr- /
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noun
a halogen element, a heavy, greenish-yellow, incombustible, water-soluble, poisonous gas that is highly irritating to the respiratory organs, obtained chiefly by electrolysis of sodium chloride brine: used for water purification, in the making of bleaching powder, and in the manufacture both of chemicals that do not contain chlorine, as ethylene glycol, and of those that do. Symbol: Cl; atomic weight: 35.453; atomic number: 17.

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Origin of chlorine

First recorded in 1800–10; chlor-1 + -ine2

OTHER WORDS FROM chlorine

chlo·rin·ous, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use chlorine in a sentence

British Dictionary definitions for chlorine

chlorine

chlorin (ˈklɔːrɪn)

/ (ˈklɔːriːn) /

noun
a toxic pungent greenish-yellow gas of the halogen group; the 15th most abundant element in the earth's crust, occurring only in the combined state, mainly in common salt: used in the manufacture of many organic chemicals, in water purification, and as a disinfectant and bleaching agent. Symbol: Cl; atomic no: 17; atomic wt: 35.4527; valency: 1, 3, 5, or 7; density: 3.214 kg/m³; relative density: 1.56; melting pt: –101.03°C; boiling pt: –33.9°C

Word Origin for chlorine

C19 (coined by Sir Humphrey Davy): from chloro- + -ine ², referring to its colour
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for chlorine

chlorine
[ klôrēn′ ]

Cl
A greenish-yellow, gaseous element of the halogen group that can combine with most other elements and is found chiefly in combination with the alkali metals as chlorates and chlorides. Chlorine is highly irritating and poisonous. It is used in purifying water, as a disinfectant and bleach, and in the manufacture of numerous chemical compounds. Atomic number 17; atomic weight 35.453; freezing point -100.98°C; boiling point -34.6°C; specific gravity 1.56 (-33.6°C); valence 1, 3, 5, 7. See Periodic Table. See Note at chlorophyll.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for chlorine

chlorine
[ (klawr-een, klawr-in) ]

A chemical element, normally a corrosive gas, that is widely used for sterilization and cleaning.

notes for chlorine

Chlorine is added to drinking water to kill bacteria.

notes for chlorine

Chlorine in CFCs is believed to be responsible for the ozone hole.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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