contaminate

American  

[kuhn-tam-uh-neyt, kuhn-tam-uh-nit, -neyt] / kənˈtæm əˌneɪt, kənˈtæm ə nɪt, -ˌneɪt /

verb (used with object)

contaminated, contaminating

1. to make impure or unsuitable by contact or mixture with something unclean, bad, etc..

   to contaminate a lake with sewage.

   Synonyms:

   corrupt, poison, infect, taint, pollute, defile

2. to render harmful or unusable by adding radioactive material to.

   to contaminate a laboratory.

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noun

1. something that contaminates or carries contamination; contaminant.

adjective

1. Obsolete. contaminated.

contaminate British  

verb

1. to make impure, esp by touching or mixing; pollute

2. to make radioactive by the addition of radioactive material

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adjective

1. archaic contaminated

Other Word Forms

• contaminable adjective
• contaminant noun
• contaminative adjective
• contaminator noun
• contaminous adjective
• noncontaminable adjective
• noncontaminative adjective
• recontaminate verb (used with object)
• self-contaminating adjective
• uncontaminable adjective
• uncontaminated adjective
• uncontaminative adjective

Etymology

Origin of contaminate

1375–1425; late Middle English contaminaten < Latin contāminātus, past participle of contāmināre to defile, spoil, equivalent to con- con- + -tāminare, verbal derivative of *tāmen something touched < *tag-s-men, equivalent to tag-, variant stem of tangere to touch + -s-men resultative noun suffix; examen

Explanation

The verb contaminate means the same as pollute. Whether it’s food, air, or water, when you contaminate something, you make it impure or hazardous. Contaminate comes from the Latin word contaminat-, meaning “made impure.” You can use the word to indicate that a hazardous substance has been introduced into something else, such as food that is contaminated with mold. It can also be used figuratively to describe the spoiling of a good thing, like one person's habit of gossiping that can contaminate a conversation among friends.

Example Sentences

The seemingly limitless proliferation of cases in which lawyers have been caught letting fictitious AI-generated legal citations contaminate their briefs continues to amaze.

From Los Angeles Times • Mar. 27, 2026

The European Medicines Agency has previously warned that these substances could contaminate ecosystems, although detailed information about how much of the drugs enter the environment remains limited.

From Science Daily • Feb. 22, 2026

Informal recycling is rife with hazards -- open burning, acid baths and unprotected dismantling expose workers to toxic fumes and contaminate soil and water.

From Barron's • Feb. 18, 2026

The aviation industry doesn’t dispute that oil and other aircraft fluids can contaminate the air on a flight, but says that the levels of chemicals released haven’t been shown to pose risk of serious illness.

From The Wall Street Journal • Dec. 23, 2025

If you haven’t been keeping the tree suspended in memory, the word islands, which is ringing in your mind’s ear just before you type the verb, will contaminate the number you give the verb.

From "The Sense of Style" by Steven Pinker

Related Words

• corrupt
• harm
• infect
• injure
• poison
• pollute
• stain
• taint
• tarnish