en·​do·​tox·​in ˌen-dō-ˈtäk-sən How to pronounce endotoxin (audio)
: a toxic heat-stable lipopolysaccharide substance present in the outer membrane of gram-negative bacteria that is released from the cell upon lysis
endotoxic adjective

Examples of endotoxin in a Sentence

Recent Examples on the Web Yet, today, LAL remains the dominant technology for detecting endotoxins in medicine. Kristoffer Whitney, Fortune Well, 13 Oct. 2023 The bacteria releases an endotoxin into the host's body, leading the host to go into septic shock. Bellamy Richardson, PEOPLE.com, 29 July 2022 Lipopolysaccharide is a fancy scientific term for an endotoxin that is a major component of the walls of certain bacteria. Patrick Wilson, Outside Online, 15 June 2020 Study subjects injected with the endotoxin were given T-shirts to wear over a few hours to capture their body odor. Sarah Everts, Time, 21 July 2021 When a panel of people smelled the collection T-shirts, panelists found the body odor of people whose immune systems had been activated by the endotoxin to be more aversive than normal body odor. Sarah Everts, Time, 21 July 2021 Because the endotoxin wasn’t actually attached to a pathogen, the study subjects’ immune systems eventually settled down. Sarah Everts, Time, 21 July 2021 The product is refined and sold as endotoxin test kits to pharmaceutical companies. Tim Prudente, baltimoresun.com, 31 Dec. 2020 While other tests exist like synthetic LAL and a human blood test, LAL bacterial endotoxin testing is the gold standard, Hoffmeister said. Doug Fraser, USA TODAY, 16 June 2020

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'endotoxin.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


International Scientific Vocabulary

First Known Use

1904, in the meaning defined above

Time Traveler
The first known use of endotoxin was in 1904

Dictionary Entries Near endotoxin

Cite this Entry

“Endotoxin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/endotoxin. Accessed 24 May. 2024.

Medical Definition


en·​do·​tox·​in ˌen-dō-ˈtäk-sən How to pronounce endotoxin (audio)
: a toxin of internal origin
specifically : a poisonous substance present in bacteria (as the causative agent of typhoid fever) but separable from the cell body only on its disintegration compare exotoxin
endotoxic adjective

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