Morbilli is the scientific term for measles, which is a highly contagious viral infection. There are several synonyms that are commonly used to describe this illness. These include rubeola, red measles, and hard measles. Rubeola is derived from the Latin word "ruber," which means red, and describes the characteristic rash that appears during the course of the illness. Hard measles refers to the severity of the symptoms, which can be quite harsh, especially in adults. Other synonyms for measles include koplik's spots and distemper. Knowing these synonyms can be helpful when discussing the illness with medical professionals or when researching information about the disease.