The six-letter word meaning “deficiency of blood or red corpuscles” is anemia. It describes a condition in which the blood has too few red blood cells, too little hemoglobin, or hemoglobin that cannot carry oxygen effectively.
Anemia is not one single disease. It can result from blood loss, reduced red-cell production, or unusually rapid destruction of red blood cells. Iron-deficiency anemia is especially common because iron is essential for making hemoglobin, the protein that transports oxygen from the lungs to body tissues. Vitamin B12 deficiency, folate deficiency, chronic disease, kidney problems, and inherited conditions such as thalassemia can also cause anemia.
The word comes from Greek roots meaning “lack of blood.” Common symptoms include fatigue, weakness, pale skin, shortness of breath, headaches, and dizziness, although slowly developing anemia may cause few obvious symptoms. A blood test measuring hemoglobin and related red-cell values is used for diagnosis.
A common mix-up is treating anemia as a synonym for iron deficiency. Iron deficiency is one cause of anemia, but anemia may occur even when iron levels are normal. British English commonly spells the word “anaemia,” while American English uses “anemia.”