tox·​in | \ˈtäk-sən \

Definition of toxin 

: a poisonous substance that is a specific product of the metabolic activities of a living organism and is usually very unstable, notably toxic when introduced into the tissues, and typically capable of inducing antibody formation

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Synonyms for toxin


bane, poison, toxic, venom

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Toxins Are Often Found in Nature

Long before chemists started creating poisons from scratch, humans were employing natural toxins for killing weeds and insects. For centuries South American tribes have used the toxin curare, extracted from a native vine, to tip their arrows. The garden flower called wolfsbane or monkshood is the source of aconite, an extremely potent toxin. The common flower known as jimsonweed contains the deadly poison scopolamine. And the castor-oil plant yields the almost unbelievably poisonous toxin called ricin. Today we hear health advisers of all kinds talk about ridding the body of toxins; but they're usually pretty vague about which ones they mean, and most of these "toxins" wouldn't be called that by biologists.

Examples of toxin in a Sentence

the toxin in scorpion venom read a pamphlet on the toxin responsible for botulism, a food poisoning that can cause paralysis and even death in some cases

Recent Examples on the Web

Thirty-two people in 11 states have been sickened by the Shiga toxin-producing E. coli O157:H7 strain, and 13 of them were hospitalized. Brian Resnick, Vox, "CDC: Don’t eat romaine lettuce. If you have any, throw it away.," 21 Nov. 2018 Farmers markets may also be a good source for finding toxin-free greens. Ashleigh Spitza, Milwaukee Journal Sentinel, "Purslane may be growing in your lawn; for better health, put it in your diet," 10 July 2018 Australian beauty brand Inika Organic might be a prize find for women of many ethnicities who want their beauty products clean, vegan and toxin-free. Kavita Daswani,, "Spruce up your spring wardrobe with these standout fashion and beauty items," 22 Mar. 2018 Five finalists presented their ideas for increasing swimming access, pop-up play exhibits, creating toxin-free lawns and gardens, and suicide prevention. Caitlin Mullen,, "'A launching point': $50,000 Big Idea award goes to group working toward educational equity in Oak Park," 13 Mar. 2018 Each subscription includes 6 boxes of toxin-free beauty and wellness products delivered to your door (ARV: $180). Woman's Day, "Love Goodly Subscription Giveaway," 7 Jan. 2017 Eventually, the toxins can damage nervous systems and lead to potential hemorrhaging and internal bleeding. Taylor Mead, House Beautiful, "How To ID The Different Kinds Of Mold In Your House—And Their Cause," 17 Sep. 2018 These toxins suppress the whales’ immune systems, making them more susceptible to disease. New York Times, "Orcas of the Pacific Northwest Are Starving and Disappearing," 9 July 2018 Salem's tap water remains off limits for certain people through the weekend, city officials said Friday, two days after an advisory tied to low-level toxins was reissued. The Oregonian/oregonlive,, "Salem water advisory extended after low-level toxins detected," 8 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'toxin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of toxin

1886, in the meaning defined above

History and Etymology for toxin

International Scientific Vocabulary

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Statistics for toxin

Last Updated

11 Dec 2018

Look-up Popularity

Time Traveler for toxin

The first known use of toxin was in 1886

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More Definitions for toxin



English Language Learners Definition of toxin

: a poisonous substance and especially one that is produced by a living thing


tox·​in | \ˈtäk-sən \

Kids Definition of toxin

: a poison produced by a living thing (as an animal or bacterium)


tox·​in | \ˈtäk-sən \

Medical Definition of toxin 

: a colloidal proteinaceous poisonous substance that is a specific product of the metabolic activities of a living organism and is usually very unstable, notably toxic when introduced into the tissues, and typically capable of inducing antibody formation

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More from Merriam-Webster on toxin

Rhyming Dictionary: Words that rhyme with toxin

Thesaurus: All synonyms and antonyms for toxin

Spanish Central: Translation of toxin

Nglish: Translation of toxin for Spanish Speakers

Britannica English: Translation of toxin for Arabic Speakers Encyclopedia article about toxin

Comments on toxin

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a soft lustrous wool fabric with mohair

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