contaminate

verb

con·​tam·​i·​nate kən-ˈta-mə-ˌnāt 

contaminated; contaminating

transitive verb

1

a

: to soil, stain, corrupt, or infect by contact or association

Bacteria contaminated the wound.

b

: to make inferior or impure by admixture

iron contaminated with phosphorus

2

: to make unfit for use by the introduction of unwholesome or undesirable elements

water contaminated by sewage

contaminative

kən-ˈta-mə-ˌnā-tiv 

adjective

contaminator

kən-ˈta-mə-ˌnā-tər 

noun

Did you know?

Contaminate, taint, pollute, and defile mean to make impure or unclean. Contaminate implies intrusion of or contact with dirt or foulness from an outside source (logically enough, it derives from the Latin word tangere, meaning "to touch"). Taint stresses a loss of purity or cleanliness that follows contact ("tainted meat"). Pollute, sometimes interchangeable with contaminate, may imply that the process which begins with contamination is complete and that what was pure or clean has been made foul, poisoned, or filthy ("the polluted waters of the river"). Defile implies befouling of what could or should have been kept clean and pure or held sacred, and commonly suggests violation or desecration ("vandals defiled the mausoleum").

Synonyms of contaminate

• pollute
• poison

Choose the Right Synonym for contaminate

contaminate, taint, pollute, defile mean to make impure or unclean.

contaminate implies intrusion of or contact with dirt or foulness from an outside source.

water contaminated by industrial wastes

taint stresses the loss of purity or cleanliness that follows contamination.

tainted meat

a politician's tainted reputation

pollute, sometimes interchangeable with contaminate, distinctively may imply that the process which begins with contamination is complete and that what was pure or clean has been made foul, poisoned, or filthy.

the polluted waters of the river

defile implies befouling of what could or should have been kept clean and pure or held sacred and commonly suggests violation or desecration.

defile a hero's memory with slanderous innuendo

Examples of contaminate in a Sentence

Be careful not to allow bacteria to contaminate the wound.

Don't touch the microchip or the oil on your hands will contaminate it.

Make sure the white paint is not contaminated by any of the other colors.

Recent Examples on the Web

That’s because there’s no way to resell prescription medications — once they’ve been received by customers, the company isn’t able to guarantee they haven’t been tampered with, opened, contaminated, or improperly stored. —Rebecca Strong, USA Today, 23 Feb. 2026

Cleaning Products and Flammable Items Bleach and other cleaning products can potentially spill or leak under the kitchen sink and contaminate other items or release fumes that may not be safe to breathe in. —Lauren Landers, The Spruce, 22 Feb. 2026

Lead pipes can corrode and contaminate drinking water. —Michael Phillis, Chicago Tribune, 21 Feb. 2026

This practice has contaminated farms, wells and food supplies in states across the country, often leaving farmers financially devastated and communities scrambling for clean drinking water. —Peter Blair, Baltimore Sun, 21 Feb. 2026

Word History

Etymology

Middle English contaminaten, borrowed from Latin contāminātus, past participle of contāmināre "to defile, pollute," from con- con- + -tāmināre, verbal derivative of *tāmen "touching, contact," going back to *tāg-(s)men, from tag-, variant stem of tangere "to touch" + *-(s)men, noun suffix of result — more at tangent entry 2

First Known Use

15th century, in the meaning defined at sense 1a

Rhymes for contaminate

• abbreviate
• accelerate
• accommodate
• accumulate
• acuminate
• adjudicate
• adulterate
• affiliate
• agglomerate
• agglutinate
• alleviate
• amalgamate

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Kids Definition

contaminate

verb

con·​tam·​i·​nate kən-ˈtam-ə-ˌnāt 

contaminated; contaminating

1

: to soil, stain, or infect by contact or association

2

: to make impure or unfit for use by adding something harmful or unpleasant

wells contaminated by chemicals

contamination

-ˌtam-ə-ˈnā-shən

noun

contaminator

-ˈtam-ə-ˌnāt-ər 

noun

Medical Definition

contaminate

transitive verb

con·​tam·​i·​nate kən-ˈtam-ə-ˌnāt 

contaminated; contaminating

1

: to soil, stain, or infect by contact or association

bacteria contaminated the wound

2

: to make unfit for use by the introduction of unwholesome or undesirable elements

water contaminated by sewage

contaminative

-ˌnāt-iv 

adjective

contaminator

-ˌnāt-ər 

noun