The objective of the páper is to inform physicians about the terminology or nomenclature of microorganisms. This along with the science of classification and identification of microorganisms is a component part of taxonomy. All newly described microorganisms háve to be named scientifically. The scientific name of a taxon in bacteriology, mycology, and parasitology is in Latin and is binomical, being subject to inter-nationally agreed-upon rules. The páper deals with the formation of the names of genera and species, námely when they are derived from proper names. Explained is why in certain cases the species name ends in a simple -i, and in other cases in a doubled -ii. The páper informs of the rule of priority and of the possibi-lity of it being applied inconsiderately. Mentioned are also problems with the pronunciation of names derived from proper names. Presented are examples of the terminology of salmonellae and leptospirae, in which for all practical reasons the term serovar is ušed instead of species. In the terminology of viruses it is pre-sumed that for the official names of species there shall be ušed their established English names.

        Key words: taxonomy - microorganisms - classification - terminology - identification.