chlorine

noun

chlo·​rine ˈklȯr-ˌēn 

-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

According to ecoHiny, its manufacturing process is elemental chlorine-free and avoids all synthetic additives, aligning with its broader goal of promoting an eco-conscious lifestyle free of toxic chemicals. —Connie Etemadi, USA Today, 24 Nov. 2025

LifeStraw’s Home 10-Cup removes microplastics, PFAS, chlorine, lead, and a laundry list of other nasties, improving both safety and taste in one pour. —Joe Jackson, Outside, 21 Nov. 2025

The gas station lacked chlorine sanitizer test strips, a repeat violation. —Veronica Fernandez-Alvarado, Sacbee.com, 21 Nov. 2025

Add 1/2 cup of baking soda to the wash to help laundry detergent and/or chlorine bleach to perform better. —Jolie Kerr, Better Homes & Gardens, 21 Nov. 2025

Word History

First Known Use

1810, in the meaning defined above

Phrases Containing chlorine

• chlorine dioxide
• chlorine monoxide

Rhymes for chlorine

• organochlorine

Kids Definition

chlorine

noun

chlo·​rine ˈklō(ə)r-ˌēn 

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 

: 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