blastomycosisPronunciation: /ˌblastə(ʊ)mʌɪˈkəʊsɪs/Definition of blastomycosis noun [mass noun] Medicine a disease caused by infection with parasitic fungi affecting the skin or the internal organs. The fungi belong to the genus Blastomyces, subdivision Deuteromycotina blastomycosis in other Oxford dictionaries Definition of blastomycosis in the US English dictionary