\ ˌär-ˈāch- 
\
\Definition of Rh factor
: any of one or more genetically determined antigens present in the red blood cells of most persons and of higher animals and capable of inducing intense immunogenic reactions
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More Definitions for Rh factor
Rh factor
nounEnglish Language Learners Definition of Rh factor
medical : a substance that is present in the red blood cells of most people
See the full definition for Rh factor in the English Language Learners Dictionary
Rh factor
noun\ ˈär-ˈāch- \
\Medical Definition of Rh factor
: a genetically determined protein on the red blood cells of some people that is one of the substances used to classify human blood as to compatibility for transfusion and that when present in a fetus but not in the mother causes a serious immunogenic reaction in which the mother produces antibodies that cross the placenta and attack the red blood cells of the fetus
— called also rhesus factor
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Time Traveler for Rh factor
The first known use of Rh factor was in 1942
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