from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. A condition marked by an abnormally large number of red blood cells in the circulatory system.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A rare disorder in which the bone marrow produces an abnormally large amount of blood cells, often red blood cells.

from The Century Dictionary and Cyclopedia

  • n. Excess of red corpuscles in the blood.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. a disorder characterized by an abnormal increase in the number of red blood cells in the blood


from The American Heritage® Dictionary of the English Language, 4th Edition

poly- + cyt(o)- + -hemia.


  • The blood cancer identified in the Tamaqua area is known as polycythemia vera - an abnormal increase in blood cells (primarily red blood cells) due to excess production of the cells by the bone marrow.

    Times Leader News

  • Murphy blamed Gans 'death on "acute hydromorphone toxicity," and said Gans also had hypertensive cardiovascular disease, a high blood pressure condition, and a condition called polycythemia that caused his red blood cell count to go up.

    KLAS - Top Story News

  • Such interventions, if fruitful in humans, might be useful against some cancers and other diseases, such as polycythemia vera, in which the body produces a life-threatening excess of blood cells. - latest science and technology news stories

  • Even professional mountaineers are at risk for experiencing "polycythemia," in which the body manufactures too many red blood cells in reaction to oxygen deprivation. high blood pressure of the lung vessels can trigger respiratory failure, which can be deadly.

    Medlogs - Recent stories

  • *Of course, I should note, for fairness, that applying leeches has considerable benefit in some cases, and the even bleeding can be of value - not only in the obvious situation of polycythemia vera, but as a very feeble but mildly effective technique in certain bacterial infections, which could have made a difference in isolated cases.

    "War of the Weasels" article in new Skeptical Inquirer - The Panda's Thumb

  • Three years ago, when she was considering a comeback, doctors found Butcher had polycythemia vera, a rare disease that causes the bone marrow to produce excess blood.

    susan butcher

  • Cobalt can cause polycythemia (i.e. above normal increases in the number of red blood cells).

    Chapter 13

  • Theoretically this transfusion of blood from the placenta to the infant might cause hypervolaemia, polycythemia and hyperviscosity, and also hyperbilirubinaemia.


  • Even in these cases the entire circulation can often be restored to normal, with normal pulmonary arterial pressures and cardiac output reduced to normal values, by vigorous symptomatic therapy, relieving bronchial obstruction, the hypoxia, hypercapnea, polycythemia and hypervolemia, and by active treatment of congestive failure.

    Dickinson W. Richards - Nobel Lecture

  • Profound arterial oxygen unsaturation leads to marked polycythemia, total blood volume increasing by the amount of the increased red cell mass.

    Dickinson W. Richards - Nobel Lecture


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  • "Indeed, bleeding—today called 'phlebotomy'—can actually help in some rare diseases, such as polycythemia, a rare genetic disorder that causes people to make too much blood, or hemachromatosis, when the blood carries too much iron."

    —John M. Barry, The Great Influenza (NY: Penguin Books, 2004), 22

    February 11, 2009