hemophilia he·mo·phil·i·a (hē'mə-fĭl'ē-ə, -fēl'yə)
Any of several hereditary blood-coagulation disorders, manifested almost exclusively in males, in which the blood fails to clot normally because of a deficiency or an abnormality of one of the clotting factors.
A hereditary disease caused by a deficiency of a substance in the blood that aids in clotting. Hemophiliacs can bleed to death even from small cuts and bruises, because their blood has largely lost the ability to clot.
Note: Queen Victoria of Britain, whose descendants have been kings and queens of several countries in Europe, carried the gene for hemophilia, which has turned up repeatedly in royal families since her lifetime. Her great-grandson, the heir to the throne of Russia, suffered from the disease, and his parents fell under the influence of the monk Grigori Rasputin in hopes of a miraculous cure. The resulting chaos in the government of Russia helped bring on the Russian Revolution and the establishment of the Soviet Union.