rh

Noun rh has 3 senses

• rh(n = noun.substance) rh factor, rhesus factor - 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;
is a kind of antigen

• rh(n = noun.substance) atomic number 45, rhodium - a white hard metallic element that is one of the platinum group and is found in platinum ores; used in alloys with platinum;
is a kind of metal, metallic element

• rh(n = noun.body) hypothalamic releasing factor, hypothalamic releasing hormone, releasing factor, releasing hormone - 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 of these hormones causes the anterior pituitary to secrete a specific hormone;
is a kind of endocrine, hormone, internal secretion