chlorine

noun

chlo·​rine ˈklȯr-ˌēn How to pronounce chlorine (audio)
-ən
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Avoid chlorine bleach as your first choice of remedy for yellowed pillowcases. — Caroline Lubinsky, Martha Stewart, 30 Aug. 2026 At the sanitation section of the triple sink/three-compartment sink, the chlorine measured 10 parts per million. — David J. Neal, Miami Herald, 28 Aug. 2026 Today, most toilet paper is produced using elemental chlorine-free (ECF) bleaching, which relies on chlorine dioxide instead of chlorine gas. — Jillian Pretzel, Time, 26 Aug. 2026 Shock the pool with a chlorine or non-chlorine shock treatment a few days before closing to help kill bacteria and prevent algae growth. — Alora Bopray, USA Today, 26 Aug. 2026 See All Example Sentences for chlorine

Word History

First Known Use

1810, in the meaning defined above

Time Traveler
The first known use of chlorine was in 1810

Phrases Containing chlorine

Rhymes for chlorine

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Browse Nearby Words

chlorinator
chlorine
chlorine demand
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Cite this Entry

“Chlorine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/chlorine. Accessed 4 Sep. 2026.

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Kids Definition

chlorine

noun
chlo·​rine ˈklō(ə)r-ˌēn How to pronounce chlorine (audio)
ˈklȯ(ə)r-, 
-ən
: a nonmetallic element that is found alone as a heavy greenish yellow irritating gas having two atoms per molecule and a strong odor and that is used especially as a bleach, oxidizing agent, and disinfectant in water purification see element

Medical Definition

chlorine

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

More from Merriam-Webster on chlorine

Britannica.com: Encyclopedia article about chlorine

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