Here's a breakdown:
* Rhesus factor (Rh factor) is a protein found on the surface of red blood cells. People who have this protein are Rh positive (Rh+), while those who don't are Rh negative (Rh-).
* Rh incompatibility can occur when an Rh-negative mother carries an Rh+ baby. During pregnancy, the mother's immune system might develop antibodies against the baby's Rh+ blood cells. This can lead to health problems for the baby, particularly in subsequent pregnancies.
* Rhesus monkey is the animal where the Rhesus factor was first discovered.
It's important to remember that "Rhesus" on its own is not a complete term. It always needs some context to be understood, like "Rhesus factor" or "Rhesus monkey."