chlorine

American  

[klawr-een, -in, klohr-] / ˈklɔr in, -ɪn, ˈkloʊr- /

noun

1. a halogen element, a heavy, greenish-yellow, incombustible, water-soluble, poisonous gas that is highly irritating to the respiratory organs, obtained chiefly by electrolysis of sodium chloride brine: used for water purification, in the making of bleaching powder, and in the manufacture both of chemicals that do not contain chlorine, as ethylene glycol, and of those that do. Cl; 35.453; 17.

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chlorine British  

/ ˈklɔːriːn, ˈklɔːrɪn /

noun

1. a toxic pungent greenish-yellow gas of the halogen group; the 15th most abundant element in the earth's crust, occurring only in the combined state, mainly in common salt: used in the manufacture of many organic chemicals, in water purification, and as a disinfectant and bleaching agent. Symbol: Cl; atomic no: 17; atomic wt: 35.4527; valency: 1, 3, 5, or 7; density: 3.214 kg/m³; relative density: 1.56; melting pt: –101.03°C; boiling pt: –33.9°C

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chlorine Scientific  

/ klôr′ēn′ /

1. A greenish-yellow, gaseous element of the halogen group that can combine with most other elements and is found chiefly in combination with the alkali metals as chlorates and chlorides. Chlorine is highly irritating and poisonous. It is used in purifying water, as a disinfectant and bleach, and in the manufacture of numerous chemical compounds. Atomic number 17; atomic weight 35.453; freezing point −100.98°C; boiling point −34.6°C; specific gravity 1.56 (−33.6°C); valence 1, 3, 5, 7.

2. See Periodic Table See Note at chlorophyll

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chlorine Cultural  

1. A chemical element, normally a corrosive gas, that is widely used for sterilization and cleaning.

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Discover More

Chlorine in CFCs is believed to be responsible for the ozone hole.

Chlorine is added to drinking water to kill bacteria.

Other Word Forms

• chlorinous adjective

Etymology

Origin of chlorine

First recorded in 1800–10; chlor- ¹ + -ine ²

Compare meaning

How does chlorine compare to similar and commonly confused words? Explore the most common comparisons:

• chlorine vs. chloride
• chloramine vs. chlorine

Example Sentences

“I smell like chlorine. So obviously I need to shower first when we get home.”

From Literature

The researchers confirmed that chlorine dioxide can kill bacteria.

From Science Daily

"They can tolerate high temperatures, strong disinfectants like chlorine, and even live inside water distribution systems that people assume are safe."

From Science Daily

These molecules are nearly identical, differing only by a single atom: fluorine, chlorine, bromine, or iodine.

From Science Daily

China has become a major supplier of ingredients for small-molecule medications, coatings and sterilization agents for medical devices, and the chlorine and caustic soda used to keep water safe to drink.

From The Wall Street Journal

Related Words

• bleach
• disinfectant