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

Combining bleach and vinegar results in the formation of chlorine gas, which is dangerous to breathe in. —Rae Ford, Martha Stewart, 5 June 2026

The Columbus Fire Department recommends that anyone who comes into contact with chlorine gas move to somewhere that has ventilation or an open-air space and remove any tight-fitting clothing. —Angel Saunders, PEOPLE, 3 June 2026

What are the symptoms of chlorine gas exposure? —Greta Cross, USA Today, 3 June 2026

Once past filtration, the sewage water is sent to be disinfected using chlorine. —Emma Hall, Sacbee.com, 3 June 2026

Word History

First Known Use

1810, in the meaning defined above

Phrases Containing chlorine

• chlorine dioxide
• chlorine monoxide

Rhymes for chlorine

• taurine
• 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