neurotoxin

noun

: a poisonous substance (such as tetrodotoxin or saxitoxin) that acts on the nervous system and disrupts the normal function of nerve cells

Did you know?

The nervous system is almost all-powerful in the body: all five senses depend on it, as do breathing, digestion, and the heart. So it's an obvious target for poisons, and neurotoxins have developed as weapons in many animals, including snakes, bees, and spiders. Some wasps use a neurotoxin to paralyze their prey so that it can be stored alive to be eaten later. Snake venom is often neurotoxic (as in cobras and coral snakes, for example), though it may instead be hemotoxic (as in rattlesnakes and coppermouths), operating on the circulatory system. Artificial neurotoxins, called nerve agents, have been developed by scientists as means of chemical warfare; luckily, few have ever been used.

Examples of neurotoxin in a Sentence

Recent Examples on the Web
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Certain areas are off-limits to crab fishing, due to high levels of neurotoxin found in the local crabs. — Anne Ewbank, Sacbee.com, 2 Nov. 2026 Caused by certain algal blooms, domoic acid is a neurotoxin that can accumulate in fish, shellfish and other invertebrates. — Tim Fang, CBS News, 2 Nov. 2026 When the neurotoxin stops suppressing nerve signals to those muscles, the lines return. — Hanna Wickes, Kansas City Star, 29 Oct. 2026 Lead is a neurotoxin that can stunt children’s development, lower IQ scores and increase blood pressure in adults. — ABC News, 28 Oct. 2026 See All Example Sentences for neurotoxin

Word History

Etymology

borrowed from French névrotoxine, from névro- neuro- + toxine toxin

First Known Use

1902, in the meaning defined above

Time Traveler
The first known use of neurotoxin was in 1902

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Cite this Entry

“Neurotoxin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/neurotoxin. Accessed 12 Nov. 2026.

Medical Definition

neurotoxin

noun
: a poisonous substance (such as tetrodotoxin or saxitoxin) that acts on the nervous system and disrupts the normal function of nerve cells

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