Borrelia burgdorferi is a bacterium responsible for causing Lyme disease in humans. It is known by several other names and synonyms such as B. burgdorferi sensu lato, B. burgdorferi sensu stricto, and Lyme Borreliosis. The bacteria is transmitted to humans through the bite of infected black-legged ticks, and symptoms may include fever, headache, and a characteristic rash. While there are several strains of Borrelia burgdorferi, they are all causative agents of Lyme disease. Due to its complex nature, the bacteria has been investigated extensively by researchers, leading to more accurate identification and treatment plans. Knowing these synonyms for Borrelia burgdorferi is essential for understanding, identifying and managing Lyme disease.