tox·​in | \ ˈtäk-sən How to pronounce toxin (audio) \

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


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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 Some cities are building new fire stations that keep toxins out of firefighters' beds and meals, and most firefighters now follow strict gear-cleaning regimens after calls. Mackenzie Shuman, azcentral, "Firefighters face an outsized risk of cancer. What is being done to keep them safe?," 11 Feb. 2020 Some gardeners know that the flowers of most vegetables and herbs are also edible (except those of tomato, potato, pepper or eggplant which contain toxins). Pam Peirce,, "Edible flowers for your garden and dinner table," 7 Feb. 2020 The fungus grows toward the hottest and most radioactive places, like phototropism but for deadly toxins. Caroline Delbert, Popular Mechanics, "You Should Know About This Chernobyl Fungus That Eats Radiation," 6 Feb. 2020 In this episode, goop’s chief content officer Elise Loehnen muses about injecting toxins into goop employees to see if Hof’s training can alter their immune systems, then bemoans the negative response from the Netflix lawyers. Jennifer Gunter, STAT, "Goop’s pseudoscience ministry comes to Netflix," 17 Jan. 2020 Microplastics, including nurdles, are also known to attract toxins that can accumulate in wildlife. Julie Grant,, "Ever hear of a nurdle? This new form of pollution could be coming to the Ohio River," 13 Jan. 2020 In a procedure called the Nefertiti Lift, injections of botulism toxin help relax the platysma muscle and provide more definition to your jaw. Kaitlyn Pirie, Good Housekeeping, "What Causes a Double Chin and How to Get Rid of It, According to a Plastic Surgeon," 7 Jan. 2020 While e-cigarettes contain and produce fewer known cancer-causing toxins than cigarettes, that’s not the only factor at play. Jamie Ducharme, Time, "Vaping Damages Your Lungs, But Is Still Safer Than Smoking, a Long-Term Study Suggests," 16 Dec. 2019 For years, scientists have suspected that the harm caused by disturbed sleep has something to do with an overaccumulation of waste products or toxins in the brain. Quanta Magazine, "Sleeping Brain Waves Draw a Healthy Bath for Neurons," 16 Dec. 2019

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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Time Traveler for toxin

Time Traveler

The first known use of toxin was in 1886

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Statistics for toxin

Last Updated

20 Feb 2020

Cite this Entry

“Toxin.” Dictionary, Merriam-Webster, Accessed 20 Feb. 2020.

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More Definitions for toxin


How to pronounce toxin (audio)

English Language Learners Definition of toxin

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


tox·​in | \ ˈtäk-sən How to pronounce toxin (audio) \

Kids Definition of toxin

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


tox·​in | \ ˈtäk-sən How to pronounce toxin (audio) \

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

Thesaurus: All synonyms and antonyms for toxin

Rhyming Dictionary: Words that rhyme with 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

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