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

The Daniel’s Mill project is a part of the Rockville Mill Complex project, which is a remediation and renovation project to repurpose and reuse contaminated 19th century textile mills for the 21st Century. —Sean Krofssik, Hartford Courant, 26 Jan. 2026

Emissions from spacecraft landings on the moon can drift freely across its surface and may settle in — and contaminate — some scientifically precious real estate, according to new research. —Sharmila Kuthunur, Space.com, 26 Jan. 2026

Some insecticide ingredients might contaminate the flowers and risk pollinator harm, even weeks or months after their application. —Miri Talabac, Baltimore Sun, 23 Jan. 2026

That notice covered an issue in which some vehicles may have leftover debris contaminating the engine’s main bearings, potentially damaging the engine and causing a loss of driving power. —Ty Roush, Forbes.com, 23 Jan. 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