toxin

American  

[tok-sin] / ˈtɒk sɪn /

noun

• toxins
  plural

1. any poison produced by an organism, characterized by antigenicity in certain animals and high molecular weight, and including the bacterial toxins that are the causative agents of tetanus, diphtheria, etc., and such plant and animal toxins as ricin and snake venom.

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toxin British  

/ ˈtɒksɪn /

noun

1. any of various poisonous substances produced by microorganisms that stimulate the production of neutralizing substances (antitoxins) in the body See also endotoxin exotoxin

2. any other poisonous substance of plant or animal origin

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toxin Scientific  

/ tŏk′sĭn /

1. A poisonous substance, especially one produced by a living organism. Toxins can be products or byproducts of ordinary metabolism, such as lactic acid, and they must be broken down or excreted before building up to dangerous levels. Toxins can facilitate survival, as with snake venom that kills or immobilizes prey, or cyanide produced by some plants as a defense against being eaten. Bacterial toxins can sometimes be neutralized with antitoxins.

2. Compare antitoxin

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Synonym Usage

See poison.

Other Word Forms

Noun Inflected Forms

• toxins
  plural

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Etymology

Origin of toxin

First recorded in 1885–90; tox(ic) + -in ²

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Explanation

A toxin is an organic poison — it’s made by plants and animals. Toxins make people sick. If your appendix bursts, toxins are released into your blood stream. Also breathing in a toxin like ricin will make you very ill. Toxins are naturally occurring poisons. There are the toxins your body creates and some that animals and plants excrete. Some are harmful — getting stung by a stingray can kill you because its toxin is powerful. Toxin is the noun form of toxic. The most dangerous kind of toxin is the botulinus toxin, which is the kind found in the bacteria of spoiled food and is used to make Botox. Another dangerous toxin, ricin, is made from castor beans.

Example Sentences

See Examples For:

toxin toxins

A single venom can contain around 100 toxin proteins belonging to multiple protein families, and venom composition differs from one snake species to another.

From Science Daily ● Sep. 8, 2026

In Austria, by contrast, botulinum toxin and dermal filler treatments are classified as medical procedures and are typically reserved for doctors.

From BBC ● Jul. 5, 2026

And then, of course, spiders are venomous, toting enough toxin to immobilize and liquify prey and, in a few cases, cause lesions, necrosis or death in humans.

From The Wall Street Journal ● May 15, 2026

France is mulling how to prevent people from ingesting too much of the heavy metal cadmium, after a warning their breakfast cereal and baguettes could be contaminated with the toxin.

From Barron's ● May 13, 2026

I look over just as Javier’s grips his hand to steady a tremble, then slides the toxin casually to the opposite side of the bench with the defoliant.

From "The Last Cuentista" by Donna Barba Higuera

After the 2025 fires, there were complaints by residents that the Fair Plan refused to test and remediate homes suffering damage by smoke, which can leave behind lead, asbestos and other toxins.

From Los Angeles Times ● Oct. 8, 2026

The scientific research in those cases involved work around the mosquito-born chikungunya virus, a "highly-pathogenic" strain of the bird flu, a family of viruses that include smallpox and mpox, venoms and other toxins.

From Barron's ● Sep. 11, 2026

Chemours, DuPont de Nemours and Corteva have settled with North Carolina and 11 communities that were excluded from a previous settlement over drinking-water toxins.

From The Wall Street Journal ● Sep. 11, 2026

It could also bind to and inhibit toxins from the venoms of several other rattlesnake species.

From Science Daily ● Sep. 8, 2026

“This flower survived in the face of chemicals and toxins, and it turned all that death into something beautiful. That miracle field, Natalie, that’s the happiest place in the world.”

From "The Science of Breakable Things" by Tae Keller

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Related Words

• contamination
• germ
• infection
• venom
• virus

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