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

Etymology

Origin of toxin

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

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

In January, Nestlé recalled some of its infant formula products after tests found they contained a toxin that can cause vomiting.

From Barron's ● Jun. 10, 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

Albayram said that in human brain microvascular endothelial cells, EPA did not act as a universal toxin.

From Science Daily ● Apr. 26, 2026

"Botulinum toxin is usually used when you've tried other treatment options, such as oral medications, and they haven't worked for you," an MS Trust spokesperson said.

From BBC ● Mar. 19, 2026

The smoke could be from a fire the First Arrivers started before the toxin was dropped.

From "The Last Cuentista" by Donna Barba Higuera

"That restorative sleep is super important for physical repair, learning and memory and washing out the toxins of the day," Macauley said.

From Science Daily ● Jul. 20, 2026

It would involve continued isolation of contaminated areas to prevent student contact and the removal of toxins through phytoremediation, an emerging technology that uses plants known to absorb toxins from the soil.

From Los Angeles Times ● Jul. 19, 2026

The toxins bred in his mind by the brutalities of war cannot be eradicated, even if he can describe his sufferings with such deceptively majestic language.

From The Wall Street Journal ● Jul. 9, 2026

This rare condition, which mostly impacts children, occurs when bacterial toxins spread throughout the body and damage red blood cells, causing clots in the organs, primarily the kidneys.

From Salon ● Jun. 22, 2026

He stinks of weed killer and fertilizer fumes, from the toxins he spent all day spraying on lawns.

From "Free Lunch" by Rex Ogle

Related Words

• contamination
• germ
• infection
• venom
• virus