hemoglobin he·mo·glo·bin (hē'mə-glō'bĭn)
The red respiratory protein of red blood cells that transports oxygen as oxyhemoglobin from the lungs to the tissues, where the oxygen is readily released and the oxyhemoglobin becomes hemoglobin.
oxyhemoglobin ox·y·he·mo·glo·bin (ŏk'sē-hē'mə-glō'bĭn)
Hemoglobin in combination with oxygen, present in arterial blood. Also called oxygenated hemoglobin.