myelocytosis

noun
my·​e·​lo·​cy·​to·​sis | \ -sī-ˈtō-səs How to pronounce myelocytosis (audio) \
plural myelocytoses\ -​ˌsēz How to pronounce myelocytoses (audio) \

Medical Definition of myelocytosis

: the presence of excess numbers of myelocytes especially in the blood or bone marrow