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thalassemia major

[mā′jər]
n.
  1. A usually fatal form of thalassemia appearing in infancy or childhood in which normal hemoglobin is absent, characterized by severe anemia, enlargement of the heart, liver, and spleen, and skeletal deformation.Cooley's anemia
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.