River blindness, also known as onchocerciasis, is a parasitic disease caused by the nematode worm Onchocerca volvulus. The infection is transmitted to humans through the bites of black flies that breed and live near fast-moving rivers and streams. The disease is characterized by intense itching, skin rashes, and irreversible blindness. Synonyms for river blindness include onchocerciasis, Robles disease, and "river eye worm." Onchocerciasis is the most commonly used synonym for river blindness, as it refers directly to the parasitic infection, while Robles disease is named after the physician who first described the disease. The "river eye worm" is a colloquial synonym used to describe the transmission process of the disease by black flies breeding in rivers and streams.