A condition characterized by abnormal thickening and hardening of bone: as a: a rare hereditary disease characterized by extreme density and hardness and abnormal fragility of the bones with partial or complete obliteration of the marrow cavities--called also Albers-Schönberg disease, marble bone disease, marble bones; b: avian leukosis of chickens marked by great enlargement and excessive calcification of the long bones especially of the legs and by more or less complete obliteration of the marrow cavities--called also marble bone, marble bone disease.
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