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Glite Dictionary
rhesus factor

rhesus factor

5.1
A substance in the blood that makes blood Rh-positive or Rh-negative
  • noun
  • /ˈriːzəs ˈfæktər/
  • Specialized
translation icon : factor Rh
  • Problems in pregnancy can arise if the mother and fetus have different rhesus factor types.

Examples

  • Blood donors are screened for their rhesus factor to ensure compatibility.

  • Do you know your rhesus factor?

  • The doctor explained that her baby was at risk due to her negative rhesus factor.

  • The rhesus factor is important in blood transfusions.

  • Blood donors are screened for their rhesus factor to ensure compatibility during transfusions.

  • Problems can occur in pregnancy if the mother and fetus have incompatible rhesus factor types.

  • The doctor explained that her baby's health was affected by her negative rhesus factor.

Synonyms

Rh
vsrhesus factor
  • Specialized
4 6.0

A protein on red blood cells that shows whether two blood types match for transfusion

is broader and also highlights importance for pregnancy compatibility
Rh factor
vsrhesus factor
  • Specialized
1 4.4

A protein on the surface of red blood cells that shows whether blood types match

is used more broadly to assess pregnancy risks as well
RhD
vsrhesus factor
  • Specialized
6.9

A protein on red blood cells that tells if blood is Rh positive or Rh negative

is the wider term covering that protein and its clinical importance

Surface Forms

rhesus factor singular
rhesus factors plural

Morphology

rhesus + factor

This is an eponymic technical term: 'rhesus' refers to a monkey species and 'factor' means an element, but their combination does not transparently indicate a blood antigen relevant to transfusions or pregnancy. As a specialized medical label rather than a compositional phrase, its meaning is not derivable from the parts and would not be predictable to a B1 learner who only knows the constituent words.

Etymology

Rhesus factor comes from early tests using blood from rhesus monkeys, where scientists found a factor (a blood substance) that made some people's blood react differently. That's why rhesus factor now means the substance that makes someone 'Rh-positive' or 'Rh-negative' and is important in blood transfusions and pregnancy.