toxin

noun

tox·​in ˈtäk-sən How to pronounce toxin (audio)
: 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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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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The reason whooping cough can bring on such a gnarly, well, cough in the first place is because of how B. pertussis wreaks havoc: These bugs latch on to the cilia (a.k.a. tiny hairlike protrusions) on cells in your respiratory tract and ooze toxins, triggering inflammation and swelling. Erica Sloan, SELF, 13 Feb. 2025 During the confirmation hearings, many senators expressed interest in efforts to address toxins and chronic health issues. Claire Bugos, Verywell Health, 13 Feb. 2025 Clostridium botulinum can produce a toxin that attacks the body’s nerves and can lead to botulism, an illness that causes breathing complications, muscle paralysis, and death, according to the U.S. Centers for Disease Control and Prevention. Bruce Gil, Quartz, 11 Feb. 2025 Botox is derived from botulinum toxin type A, a toxin that’s produced from the bacterium Clostridium botulinum. Caroline C. Boyle, USA TODAY, 9 Feb. 2025 See all Example Sentences for toxin 

Word History

Etymology

International Scientific Vocabulary

First Known Use

1887, in the meaning defined above

Time Traveler
The first known use of toxin was in 1887

Dictionary Entries Near toxin

Cite this Entry

“Toxin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/toxin. Accessed 21 Feb. 2025.

Kids Definition

toxin

noun
tox·​in ˈtäk-sən How to pronounce toxin (audio)
: a substance produced by a living organism (as a bacterium) that is very poisonous to other organisms and that usually causes antibody formation compare antitoxin
Etymology

derived from Latin tox- "poisonous" and English -in "chemical compound"; tox- from toxicum "poison," from Greek toxikon "arrow poison," from toxon "bow, arrow" — related to intoxicate, toxic see Word History at intoxicate

Medical Definition

toxin

noun
tox·​in ˈtäk-sən How to pronounce toxin (audio)
: 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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