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[an-uh-fuh-lak-sis] /ˌæn ə fəˈlæk sɪs/
noun, Pathology.
exaggerated allergic reaction to a foreign protein resulting from previous exposure to it.
Origin of anaphylaxis
First recorded in 1905-10; ana- + (pro)phylaxis
Related forms
[an-uh-fuh-lak-tik] /ˌæn ə fəˈlæk tɪk/ (Show IPA),
anaphylactically, adverb
antianaphylactic, adjective, noun
pseudoanaphylactic, adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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British Dictionary definitions for anaphylaxis


extreme sensitivity to an injected antigen, esp a protein, following a previous injection
Derived Forms
anaphylactic, anaphylactoid, adjective
anaphylactically, adverb
Word Origin
C20: from ana- + (pro)phylaxis
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for anaphylaxis
Online Etymology Dictionary, © 2010 Douglas Harper
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anaphylaxis in Medicine

anaphylaxis an·a·phy·lax·is (ān'ə-fə-lāk'sĭs)
n. pl. an·a·phy·lax·es (-lāk'sēz)

  1. Hypersensitivity induced by preliminary exposure to a substance and usually producing a contraction of smooth muscle and a dilation of blood vessels.

  2. See anaphylactic shock.

an'a·phy·lac'tic (-lāk'tĭk) adj.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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anaphylaxis in Science
See anaphylactic shock.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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