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.
Additionally, Valdes says to steer clear of abrasive shampoos and swimming pools—chlorine can mess with your color. Lisa Desantis, Glamour, 22 May 2025 Routine tests are ran every few hours to check water quality through pH, chlorine, phosphate, fluoride, alkalinity, total hardness, calcium hardness, turbidity and the Langelier Saturation Index, which determines water balance. Olivia Stevens, Chicago Tribune, 30 Apr. 2025 Step 8: Shock The Pool Shocking the pool with a high amount of chlorine will kill off any bacteria and algae in the water. Brandee Gruener, Southern Living, 21 Apr. 2025 Plant nutrients that are needed in much lower quantities are boron, calcium, chlorine, copper, iron, magnesium, manganese, molybdenum, sulfur and zinc. Rita Perwich, San Diego Union-Tribune, 1 Mar. 2025 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

Cite this Entry

“Chlorine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/chlorine. Accessed 29 May. 2025.

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
: 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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