"Black fever" is an outdated term used to describe the infectious disease known as visceral leishmaniasis. This disease is caused by the Leishmania parasite and is transmitted through the bites of infected sand flies. More current and accurate synonyms for "black fever" include kala-azar, dum-dum fever, and visceral leishmaniasis. Kala-azar, meaning "black fever" in Hindi, is commonly used in India where the disease is still prevalent. Dum-dum fever was named after the location where the disease was first studied in India. Using accurate and current terminology can help improve understanding and awareness of this serious and potentially deadly disease.