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reagin

American  
[ree-ey-jin, -gin] / riˈeɪ dʒɪn, -gɪn /

noun

Immunology.

  1. Also called Wassermann antibody.  an antibody formed in response to syphilis and reactive with cardiolipin in various blood tests for the disease.

  2. an antibody found in certain human allergies, as hay fever and asthma.

reagin British  
/ ˈrɪədʒɪn /

noun

  1. immunol a type of antibody that is formed against an allergen and is attached to the cells of a tissue. The antigen–antibody reaction that occurs on subsequent contact with the allergen causes tissue damage, leading to the release of histamine and other substances responsible for an allergic reaction

"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

Etymology

Origin of reagin

1910–15; < German Reagin, equivalent to reag ( ieren ) to react + -in -in 2

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.