Molecular phylogenetic analysis confirmed the phylum Zygomycota to be polyphyletic, and the taxa conventionally classified in Zygomycota are now distributed among the new phylum Glomeromycota and 4 subphyla incertae sedis (uncertain placement). Because the nomenclature of the disease zygomycosis was based on the phylum Zygomycota (Zygomycetes) in which the etiologic agents had been classified, the new classification profoundly affects the name of the disease. Zygomycosis was originally described as a convenient and inclusive name for 2 clinicopathologically different diseases, mucormycosis caused by members of Mucorales and entomophthoramycosis caused by species in the order Entomophthorales of Zygomycota. Without revision of original definition, the name "zygomycosis," however, has more often been used as a synonym only for mucormycosis. This article reviews the progress and changes in taxonomy and nomenclature of Zygomycota and the disease zygomycosis. The article also reiterates the reasons why the classic names "mucormycosis" and "entomophthoramycosis" are more appropriate than "zygomycosis."