disinfectant

noun

dis·​in·​fec·​tant ˌdis-in-ˈfek-tənt 

plural disinfectants

: an agent used to disinfect something

especially : a chemical agent that is used especially on hard surfaces and in water (such as drinking water or wastewater) to destroy, inactivate, or significantly reduce the concentration of pathogens (such as bacteria, viruses, and fungi)

Note: Common chemical disinfectants include chlorine, calcium and sodium hypochlorite, iodophor, phenol, ethanol, and quaternary ammonium compounds. Disinfectants are often distinguished from sterilants by having reduced effectiveness against dormant bacterial endospores.

Examples of disinfectant in a Sentence

They use a strong disinfectant on the medical equipment.

Clean the area with disinfectant.

Recent Examples on the Web

Next, Mock recommends disinfecting the can by either spraying it with disinfectant or applying a solution of 1/8 cup bleach and one quart hot water and scrubbing the entire can well. —Melissa Locker, Southern Living, 2 Sep. 2025

And some travelers, especially those going to the Maldives, Australia, and other countries that spray insecticide and disinfectant on arriving flights, wrap their luggage in plastic to protect their contents from the chemicals. —Katie Jackson, Travel + Leisure, 1 Sep. 2025

The school's staff lounge was also affected, but that room was able to be cleaned with bleach and disinfectant, according to Elliott. —Alec Johnson, jsonline.com, 30 Aug. 2025

According to medical aid groups and Israel's Physicians for Human Rights, Israel argues that items including hospital beds, anesthesia and water disinfectant tablets could have military use. —Jane Arraf, NPR, 28 Aug. 2025

Word History

First Known Use

1837, in the meaning defined above

Rhymes for disinfectant

• expectant
• protectant

Kids Definition

disinfectant

noun

dis·​in·​fect·​ant

dis-ᵊn-ˈfek-tənt

: something (as a chemical) that is able to destroy harmful germs (as bacteria and fungi)

disinfectant adjective

Medical Definition

disinfectant

1 of 2 noun

dis·​in·​fec·​tant -ˈfek-tənt 

: an agent (as a chemical or ultraviolet light) that destroys, inactivates, or significantly reduces the concentration of pathogens (as bacteria, viruses, and fungi) especially on hard surfaces and in water (as drinking water or wastewater)

also : a preparation or formulation containing one or more disinfectants along with additional additives (as water and fragrance)

Note: Common chemical disinfectants include chlorine, calcium and sodium hypochlorite, iodophor, phenol, ethanol, and quaternary ammonium compounds. Disinfectants are often distinguished from sterilants by having reduced effectiveness against dormant bacterial endospores.

disinfectant

2 of 2 adjective

: serving or tending to disinfect : suitable for use in disinfecting