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

transitive verb

: 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
: 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
: 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

Example Sentences

Chemicals were added to disinfect the water. The wound needs to be disinfected.
Recent Examples on the Web Once your tools are sharp, disinfect them by wiping them with 70% alcohol or dipping them in a 10% bleach solution. Beth Botts, Chicago Tribune, 18 Mar. 2023 This will disinfect and remove any residual smells. Sara Rodrigues, House Beautiful, 14 Mar. 2023 Buy It: Method All-Purpose Cleaner Concentrate Kit ($18, Method) Best Disinfectant This reliable spray can disinfect pretty much any germ-collecting surface. Katy Kiick Condon, Better Homes & Gardens, 13 Mar. 2023 The sun can, for instance, naturally disinfect surfaces while gloomier days help viral particles survive on surfaces contaminated by infected bird poop, Lorenzoni said. Denise Chow, NBC News, 18 Jan. 2023 The acid in a vinegar cleaning solution can remove lime scale when regularly cleaning your humidifier but in order to disinfect it a hydrogen peroxide solution soak is recommended. Dallas News, 12 Jan. 2023 Consider materials that cushion your joints from impact (like how running on grass is better for your knees than running on asphalt) and are easy to disinfect or wipe down. Kathleen Willcox, Popular Mechanics, 22 Dec. 2022 Scrub the pots with a solution of one part bleach to 10 parts water to disinfect them if necessary because of a disease problem. Tim Johnson, Chicago Tribune, 27 Nov. 2022 The final step is to disinfect the exterior parts of the toilet. Susannah Herrada, Washington Post, 3 Nov. 2022 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'disinfect.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

Dictionary Entries Near disinfect

Cite this Entry

“Disinfect.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/disinfect. Accessed 31 Mar. 2023.

Kids Definition


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

Medical Definition


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
Last Updated: - Updated example sentences
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