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Rh factor

[ ahr-eych-fak-ter ]
/ ˈɑrˈeɪtʃ ˌfæk tər /
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noun Physiology.
an inherited antigen found on the red blood cells of most people and certain other primates: those with this antigen are Rh positive while those lacking it are Rh negative , the determination of which is especially important when assessing blood-type compatibility for transfusions and pregnancy.
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Also called Rh .

Origin of Rh factor

First recorded in 1940–45; so called because first found in the blood of rhesus monkeys

Words nearby Rh factor

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use Rh factor in a sentence

British Dictionary definitions for Rh factor

Rh factor

noun
an agglutinogen commonly found in human blood: it may cause a haemolytic reaction, esp during pregnancy or following transfusion of blood that does not contain this agglutinogenFull name: rhesus factor See also Rh positive, Rh negative

Word Origin for Rh factor

C20: named after the rhesus monkey, in which it was first discovered
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

Scientific definitions for Rh factor

Rh factor
[ ärāch ]

Any of several antigens present on the surface of red blood cells in most humans. People with Rh factors are classified as having a blood type that is Rh positive, while people who lack the antigen are said to be Rh negative and can produce powerful antibodies that destroy red blood cells if given a blood transfusion from an Rh-positive donor. A woman who is Rh negative and is pregnant with an Rh-positive fetus can produce antibodies that are life threatening to the fetus. See Note at blood type.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for Rh factor

Rh factor
[ (ahr-aych) ]

Any of several substances found on the surface of red blood cells in persons.

notes for Rh factor

An Rh-negative woman who gives birth to an Rh-positive baby may develop antibodies to the Rh factor during her first pregnancy. These antibodies may cause a disorder in Rh-positive babies conceived afterward that could result in the death of the infant if the condition is not recognized and treated.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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