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

The team discovered that when pest control successfully reduced cockroach numbers, both allergen and endotoxin levels dropped sharply.

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

The European Pharmacopeia approved rFC for endotoxin testing last year.

From Washington Post • Jul. 30, 2021

Lonza said its rFC product, PyroGene, now accounts for less than 5 percent of its endotoxin test sales but sees fortunes changing as global pharmacopoeias act.

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