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

Rather than maintaining a substantial supply of single-stranded DNA and toxin before infection, these retrons produce little detectable DNA and no noticeable amount of toxin in healthy cells.

From Science Daily ● Oct. 31, 2026

For nearly two decades, scientists have known that a common gut bacterium can produce a toxin that damages the colon and helps drive the formation of tumors.

From Science Daily ● Oct. 31, 2026

Their findings, published in Nature, identify a protein called claudin-4 as the essential docking point for a bacterial toxin known as BFT.

From Science Daily ● Oct. 31, 2026

Although BFT could break down E-cadherin, the toxin did not appear to attach directly to that protein.

From Science Daily ● Oct. 31, 2026

Curare, the officer explained, a highly lethal toxin.

From "Fallout: Spies, Superbombs, and the Ultimate Cold War Showdown" by Steve Sheinkin

While the cane toad is not a direct threat to Rio Tinto's business, it produces toxins lethal to native wildlife and poses a threat to Pilbara's ecosystem.

From BBC ● Nov. 3, 2026

Despite decades of research into salamander toxins and skin chemistry, the newly observed fluorescence came as a surprise.

From Science Daily ● Oct. 28, 2026

While the team ultimately failed to achieve that universal moonshot goal, the broader experiment still managed to produce 17 working proteins that successfully bound to four of the targeted individual toxins.

From MarketWatch ● Oct. 20, 2026

But in times of heat stress, algae can produce toxins, forcing their hosts to expel them.

From Barron's ● Oct. 14, 2026

They cut HeLa cells apart and exposed them to endless toxins, radiation, and infections.

From "The Immortal Life of Henrietta Lacks" by Rebecca Skloot

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Related Words

• contamination
• germ
• infection
• venom
• virus

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