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[ek-soh-tok-sin] /ˌɛk soʊˈtɒk sɪn/
noun, Biochemistry
a soluble toxin excreted by a microorganism.
Compare endotoxin.
1915-20; exo- + toxin
Related forms
exotoxic, adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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British Dictionary definitions for exotoxic


a toxin produced by a microorganism and secreted into the surrounding medium
Derived Forms
exotoxic, adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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exotoxic in Medicine

exotoxic ex·o·tox·ic (ěk'sō-tŏk'sĭk)

  1. Relating to an exotoxin.

  2. Relating to the introduction of an exogenous poison or toxin.

exotoxin ex·o·tox·in (ěk'sō-tŏk'sĭn)
A toxin secreted by a microorganism and released into the environment in which it grows. Also called extracellular toxin.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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Encyclopedia Article for exotoxic


a poisonous substance secreted by certain bacteria. In their purest form they are the most potent poisons known and are the active agents in diphtheria, tetanus, and botulism. The term is now sometimes restricted to poisonous proteins that are antigenic-i.e., that stimulate the formation of antibodies-and formed by gram-positive bacteria. Compare endotoxin.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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