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disinfect

verb

dis·​in·​fect ˌdis-in-ˈfekt How to pronounce disinfect (audio)
disinfected; disinfecting; disinfects

transitive verb

1
: to cleanse (a surface, a device, a supply of water, etc.) by destroying, inactivating, or significantly reducing the concentration of pathogenic agents (such as bacteria, viruses, and fungi) : to treat (something) with a disinfectant (such as chlorine, hydrogen peroxide, or sodium hypochlorite)
… medical experts say some scopes can be difficult to disinfect through conventional cleaning because of their design, so bacteria are transmitted from patient to patient.Chad Terhune
Trihalomethanes are chemicals formed when chlorine used to disinfect water reacts with organic matter, such as animal waste, treated sewage, leaves, or soil.Emily Main
Clean your humidifier often. Although some parts may be washable in the dishwasher, they still need to be descaled with vinegar and disinfected with bleach.Consumer Reports
2
: to relieve (something) of some undesirable quality likened to a disease or infection
But the big question is this: If the bill becomes law, will it truly disinfect our politics?Nancy Gibbs and Karen Tumulty
3
: to remove a software virus (see virus sense 3) from (a computer or device) often by means of a special program
The earliest viruses were relatively simple routines, and virus detectors could easily disinfect computers.Philips Chien

Examples of disinfect in a Sentence

Chemicals were added to disinfect the water. The wound needs to be disinfected.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Overnight, dictionaries announced new norms, as if speech could be disinfected. Literary Hub, 24 Nov. 2025 Unlike the refrigerator thawing method, a turkey thawed in cold water thawed must be cooked immediately after thawing, and be sure to thoroughly disinfect your sink, if used. Catherine Jessee, Southern Living, 23 Nov. 2025 The Washington State Department of Health urges people cleaning up around bird feeders and other areas exposed to bird feces to wear gloves and disinfect the area with a mixture of one part bleach to 10 parts water or a commercial disinfectant like Lysol spray. Jen Christensen, CNN Money, 14 Nov. 2025 Just a couple of spritzes disinfect her hands without drying them out, thanks to moisturizing ingredients like niacinamide and centella asiatica. Rylee Johnston, Travel + Leisure, 14 Nov. 2025 See All Example Sentences for disinfect

Word History

Etymology

Middle French desinfecter, from des- dis- + infecter to infect

First Known Use

1658, in the meaning defined at sense 1

Time Traveler
The first known use of disinfect was in 1658

Browse Nearby Words

Cite this Entry

“Disinfect.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/disinfect. Accessed 29 Nov. 2025.

Kids Definition

disinfect

verb
dis·​in·​fect ˌdis-ᵊn-ˈfekt How to pronounce disinfect (audio)
: to cleanse of germs that might cause disease
disinfection noun

Medical Definition

disinfect

transitive verb
dis·​in·​fect ˌdis-ᵊn-ˈfekt How to pronounce disinfect (audio)
: to destroy, inactivate, or significantly reduce the concentration of pathogenic agents (as bacteria, viruses, and fungi) especially on hard surfaces and in water : to treat (something) with a disinfectant (as chlorine, hydrogen peroxide, or sodium hypochlorite)
disinfection noun

More from Merriam-Webster on disinfect

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