endotoxin

American  

[en-doh-tok-sin] / ˌɛn doʊˈtɒk sɪn /

noun

Biochemistry.

1. the toxic protoplasm liberated when a microorganism dies and disintegrates, as in Eberthella typhi, the causative agent of typhoid fever.

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endotoxin British  

/ ˌɛndəʊˈtɒksɪn /

noun

1. a toxin contained within the protoplasm of an organism, esp a bacterium, and liberated only at death

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Other Word Forms

• endotoxic
  adjective

Etymology

Origin of endotoxin

First recorded in 1900–05; endo- + toxin

Compare meaning

How does endotoxin compare to similar and commonly confused words? Explore the most common comparisons:

• endotoxin vs. exotoxin

Example Sentences

"Past surveys in U.S. homes found endotoxin levels much higher in homes with self-reported evidence of cockroaches; that association is stronger in low-income homes than in single-family homes."

From Science Daily • Nov. 4, 2025

After the pharmacist first testified the drugs are tested for endotoxins, the investigation found he later said he didn’t know endotoxin testing was required, Henry wrote.

From Seattle Times • Jan. 25, 2023

“As it is now, the entire supply chain for endotoxin testing of drugs rests upon the harvest of a vulnerable or near extinct sea creature,” Williams said.

From Washington Post • Jul. 30, 2021

Scientists harnessed nature’s ingenuity, using crab blood to make so-called amebocyte lysate endotoxin tests which, by the 1970s, began displacing tests on rabbits that were injected with medicine then monitored for fever.

From Reuters • Aug. 1, 2019

It is when confronted by the overwhelming signal of free molecules of endotoxin, evoking memories of vibrios in great numbers, that the limulus flies into panic, launches all his defenses at once, and destroys himself.

From "The Lives of a Cell" by Lewis Thomas