What does chlorinating mean?
"Chlorinating" is the present participle of the verb "chlorinate," meaning to treat a substance — most often drinking water or swimming-pool water — with chlorine in order to kill harmful bacteria, viruses, and other pathogens. It also has a narrower chemical sense, describing reactions in which chlorine atoms are introduced into a compound. The practice of chlorinating municipal water supplies began in the late nineteenth and early twentieth centuries and is widely credited with dramatically reducing deaths from waterborne diseases such as cholera and typhoid. Today the word appears mainly in technical and professional settings: water-treatment engineers speak of chlorinating reservoirs, pool technicians of chlorinating spa water, and chemists of chlorinating organic molecules in synthesis. While it carries little emotional weight, the term can surface in debates about food processing and water safety, where attitudes toward chlorination vary between countries. Related forms include "chlorinate," "chlorinated," and "chlorination."
Treating something, especially water, with chlorine to disinfect it, or combining a substance with chlorine in a chemical reaction.
"Engineers have been chlorinating the reservoir all week following traces of contamination."
Used transitively; the object is usually the substance being treated rather than the chlorine itself.
The act or process of adding chlorine to a substance, especially as a method of disinfection.
"Chlorinating remains the most cost-effective safeguard against waterborne disease worldwide."
That classic 'pool smell' isn't actually chlorine — it's chloramines, formed when chlorine reacts with sweat and urine, so a strongly smelling pool may be the one that's been least freshly chlorinated.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of chlorinating
"Chlorinating" derives from "chlorinate," which combines "chlorine" with the verb-forming suffix "-ate." "Chlorine" itself was coined in the early nineteenth century from the Greek "chloros," meaning pale green or yellowish-green, a reference to the gas's distinctive color. The word belongs to a family of chemical terms built on the same Greek root, including "chloride," "chloroform," and "chlorophyll" (literally "green leaf"). As chlorine chemistry developed through the 1800s, "chlorinate" became established both for disinfection and for chemical reactions involving chlorine.
Related word forms
How chlorinating is actually used
"Chlorinating" is chiefly a technical and professional term used in water treatment, swimming-pool maintenance, chemistry, and public-health contexts; everyday speakers more often say they are "putting chlorine" in something. The word carries no emotional connotation, though it can evoke institutional hygiene or, in some circles, concern about chemical additives such as chlorinated chicken.
Easily confused with chlorinating
Chlorine is the greenish-yellow gaseous chemical element itself, while chlorinating is the action of adding that element to something.
Clarifying means making a liquid clear by removing impurities generally; chlorinating specifically means treating it with chlorine, which disinfects but does not necessarily clarify.