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Rh positive

or Rh-positive

[ahr-eych poz-i-tiv] /ˈɑrˈeɪtʃ ˈpɒz ɪ tɪv/
See under Rh factor.
Origin of Rh positive
First recorded in 1955-60

Rh factor

[ahr-eych fak-ter] /ˈɑrˈeɪtʃ ˌfæk tər/
noun, Physiology.
any of a type of specific antigen present on the surface of red blood cells, persons having inherited such antigens being designated Rh+ (Rh positive) and persons lacking them, a much smaller group, being designated Rh− (Rh negative) blood of Rh− persons is incompatible with Rh+ blood because of antibody reaction, and an Rh− woman who bears an Rh+ baby will have formed antibodies to the fetal blood that, unless removed from her bloodstream by apheresis in a subsequent pregnancy, will be carried across the placenta and destroy red blood cells of the next Rh+ fetus, resulting in erythroblastosis in the newborn.
First recorded in 1940-45; so called because first found in the blood of rhesus monkeys Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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British Dictionary definitions for rh-positive

Rh positive

blood containing the Rh factor
a person having such blood

Rh factor

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 agglutinogen Full name rhesus factor See also Rh positive, Rh negative
Word Origin
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
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Word Origin and History for rh-positive

Rh factor

1942, from the first letters of rhesus; so called because the blood group, and its effects, were discovered in the blood of rhesus monkeys (1941).

Online Etymology Dictionary, © 2010 Douglas Harper
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rh-positive in Medicine

Rh-positive adj.
Containing an Rh factor.

Rh factor n.
Any of several substances on the surface of red blood cells that induce a strong antigenic response in individuals lacking the substance.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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rh-positive in Science
Rh factor
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 © 2002. Published by Houghton Mifflin. All rights reserved.
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rh-positive in Culture
Rh factor [(ahr-aych)]

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

Note: 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 Company.
Published by Houghton Mifflin Company. All rights reserved.
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