The article studies the vocabulary used in epidemiology and infectious diseases, an integral part of the Ukrainian terminology system. It addresses the issue of whether these terms comply with the requirements of the terminological norm. The lexical and semantic features and inter-changeability of such lexemes are clarified. The terminology in epidemiology and infectious diseases encompasses designations for processes, conditions, disease names, substances, enzymes, allergens, toxins, vaccines, viruses, bacteria, scientific disciplines, subfields, professional titles, individuals, and medical instruments. The analysis indicates that the reviewed terms generally comply with the features of the terminological norm, as they correlate with the concepts they denote, are part of the medical terminology system, have clear definitions in dictionaries, and are stylistically neutral. However, specific terms do not fully meet the criteria of unambiguity, as some exhibit polysemy while others demonstrate synonymy, with both foreign-origin terms and their Ukrainian equivalents being identified.