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.
Oxygen Bleach Oxygen bleach, such as sodium percarbonate, is a safe and effective alternative to chlorine bleach for whitening towels. — Anyssa Roberts, The Spruce, 28 Oct. 2026 The Sani bucket for towels lacked the chlorine solution at 50-100 ppm. — Arkansas Online, 26 Oct. 2026 The problem, however, is its high chloride content, which can corrode electrodes and other electrolyzer components, and also trigger unwanted reactions that produce toxic chlorine compounds. — New Atlas, 24 Oct. 2026 Endurance testing Heating the material triggers a chemical reaction that removes loose chlorine ions and forms strong bonds between indium, oxygen, and phosphorus. — Mrigakshi Dixit, Interesting Engineering, 23 Oct. 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 2 Nov. 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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