chlo·​rine | \ ˈklȯr-ˌēn How to pronounce chlorine (audio) , -ən \

Definition of chlorine

: a halogen element that is isolated as a heavy greenish-yellow diatomic gas of pungent odor and is used especially as a bleach, oxidizing agent, and disinfectant in water purification — see Chemical Elements Table

Examples of chlorine in a Sentence

Recent Examples on the Web That wouldn’t present a problem to much of the state, where groundwater in community wells is disinfected with chlorine or ultraviolet light, for example, and treated many times before it is ever used for drinking. Greg Stanley, Star Tribune, "Minnesota well water tests show no evidence of coronavirus," 13 Oct. 2020 The next morning, the explosion and fire at the BioLab chlorine plant about five miles away forced them to stay inside their wrecked house as toxic clouds billowed into the air for hours. Tony Mcauley,, "New Orleans opens its arms, and hotels, to thousands of Laura evacuees on Katrina anniversary," 29 Aug. 2020 More on Hurricane Laura next week (and more on fires later in this newsletter), but for now, there's a developing story out of Louisiana where a chemical fire at a chlorine plant erupted not long after the storm swept through the area. Mark Olalde, USA TODAY, "Climate Point: Buckle up, we're entering the age of super-charged weather," 28 Aug. 2020 The chemical fire that erupted in the BioLab chlorine plant — sending black clouds laced with toxic gases into the sky — was still smoldering Friday, as state hazmat crews struggled to extinguish it. Washington Post, "Hurricane Laura didn’t cause pollution in Louisiana town. It just added to it.," 28 Aug. 2020 On the other hand, swimming was being allowed after the Centers for Disease Control backed the science that chlorine stopped the spread of the coronavirus. Joshua Q. Nelson, Fox News, "NJ high school swimmers push back after governor's suspension of indoor sports," 2 Dec. 2020 The current method of treating the water, chlorine, leaves toxic disinfectant byproducts behind, making the water treatment process a delicate balancing act, Kelson said. London Gibson, The Indianapolis Star, "'Will we have water when we need it?': How Indiana utilities are preparing for climate change," 24 Nov. 2020 An attack of this style would be reminiscent of the cyberattacks on the Israeli Water Authority from earlier this year, which attempted to alter the chlorine levels of the country’s public water supply. Guilad Regev, Fortune, "How bad actors could sabotage a COVID vaccine—and how that can be prevented," 18 Nov. 2020 Screw the lid back on tight, and wipe the exterior of the bottle to get the chlorine on all surfaces. Popular Science, "Wood filters, hot rocks, and seven other ways to purify water in the wild," 2 Nov. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'chlorine.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of chlorine

1810, in the meaning defined above

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Time Traveler for chlorine

Time Traveler

The first known use of chlorine was in 1810

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Statistics for chlorine

Last Updated

12 Jan 2021

Cite this Entry

“Chlorine.” Dictionary, Merriam-Webster, Accessed 22 Jan. 2021.

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More Definitions for chlorine


How to pronounce chlorine (audio)

English Language Learners Definition of chlorine

: a chemical that in its natural form is a greenish-yellow gas and has a strong smell


chlo·​rine | \ ˈklȯr-ˌēn How to pronounce chlorine (audio) , -ən \

Kids Definition of chlorine

: a chemical element that is a greenish yellow irritating gas of strong odor used as a bleach and as a disinfectant to purify water


chlo·​rine | \ ˈklō(ə)r-ˌēn, ˈklȯ(ə)r-, -ən How to pronounce chlorine (audio) \

Medical Definition of chlorine

: a halogen element that is isolated as a heavy greenish yellow gas of pungent odor and is used especially as a bleach, oxidizing agent, and disinfectant in water purification symbol Cl — see Chemical Elements Table

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More from Merriam-Webster on chlorine

Nglish: Translation of chlorine for Spanish Speakers

Britannica English: Translation of chlorine for Arabic Speakers Encyclopedia article about chlorine

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