Rh /ˌɑrˈeʧ/



 Rh
      n 1: a blood group antigen possessed by Rh-positive people; if an
           Rh-negative person receives a blood transfusion from an
           Rh-positive person it can result in hemolysis and anemia
           [syn: rhesus factor, Rh factor]
      2: a white hard metallic element that is one of the platinum
         group and is found in platinum ores; used in alloys with
         platinum [syn: rhodium, atomic number 45]
      3: any of several hormones produced in the hypothalamus and
         carried by a vein to the anterior pituitary gland where
         they stimulate the release of anterior pituitary hormones;
         each releasing hormone causes the anterior pituitary to
         secrete a specific hormone [syn: releasing hormone, {releasing
         factor, hypothalamic releasing hormone, {hypothalamic
         releasing factor]