myelosis
/ˌmʌɪəˈləʊsɪs/Pathology
noun
1Originally: abnormal proliferation of white blood cell (granulocyte) precursors; an instance of this. Later also (chiefly with distinguishing word): abnormal proliferation of erythroid precursors or megakaryocytes.
2Degenerative disease of the spinal cord; specifically (in full funicular myelosis) degeneration of the posterior and lateral columns, sometimes associated with pernicious anaemia.
Origin
Mid 19th century (in an earlier sense). From myelo- + -osis. In sense 3, after German Myelosis, Myelose.