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

noun Immunology.

Also called Wassermann antibody. an antibody formed in response to syphilis and reactive with cardiolipin in various blood tests for the disease.
an antibody found in certain human allergies, as hay fever and asthma.

Origin of reagin

1910–15; < German Reagin, equivalent to reag(ieren) to react + -in -in2 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for reagin

/ (ˈrɪədʒɪn) /


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

Word Origin for reagin

C20: from German reagieren to react + -in
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

Medicine definitions for reagin

[ rē-ājĭn ]


An antibody found in the blood of individuals having a genetic predisposition to allergies such as asthma and hay fever.
A substance present in the blood of individuals having a positive serological test for syphilis.

Other words from reagin

re′a•ginic (rē′ə-jĭnĭk) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.