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

Scotland’s public water utility has recently become the first in the world to adopt a new technology that can convert contaminated laboratory plastics into material suitable for recycling. — Georgina Jedikovska, Interesting Engineering, 20 Aug. 2026

In addition, John’s handling of the body contaminated some of the evidence. — Encyclopedia Britannica, 20 Aug. 2026

Untreated sewage, industrial waste and debris from Mexico into the Tijuana River and southern San Diego has exposed thousands of San Diego residents to contaminated air and water. — Samhita M Ilango, San Diego Union-Tribune, 19 Aug. 2026

At least 431 people in 32 states have gotten sick from eating fresh jalapeño peppers contaminated with salmonella, the Centers for Disease Control and Prevention reported Wednesday. — Erika Edwards, NBC news, 19 Aug. 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