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

When a phage infects the bacterium, it disrupts this protective arrangement, allowing the toxin to act.

From Science Daily ● Oct. 31, 2026

Even more promising, the researchers have already used this discovery to develop a molecular decoy that intercepts the toxin before it can damage colon cells.

From Science Daily ● Oct. 31, 2026

The team systematically switched off genes in colon epithelial cells, the cells that form the inner lining of the colon, to determine which ones were necessary for the toxin to attach and cause damage.

From Science Daily ● Oct. 31, 2026

"It's almost the mirror-image version of how we traditionally view retrons, because the DNA switches on toxin production instead of inhibiting an already-produced toxin," Zhang says.

From Science Daily ● Oct. 31, 2026

“I will need access to the toxin supply to make the changes.”

From "The Last Cuentista" by Donna Barba Higuera

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

His heart beats and his eyelids blink and he breathes and his kidneys process toxins and he talks, and all of it utterly involuntary.

From "Will Grayson, Will Grayson" by John Green and David Levithan

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Related Words

• contamination
• germ
• infection
• venom
• virus

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