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

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

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