Elizabeth Short (July 29, 1924 – c. January 15, 1947), known posthumously as the Black Dahlia, was an American woman found murdered in the Leimert Park neighborhood of Los Angeles on January 15, 1947. Her case became highly publicized due to the gruesome nature of the crime, which included the mutilation of her corpse, which was bisected at the waist.

A native of Boston, Short spent her early life in New England and Florida before relocating to California, where her father lived. It is commonly held that Short was an aspiring actress, though she had no known acting credits or jobs during her time in Los Angeles. She would acquire the nickname of the Black Dahlia posthumously, as newspapers of the period often nicknamed particularly lurid crimes; the term may have originated from a film noir murder mystery, The Blue Dahlia, released in 1946. After the discovery of her body, the Los Angeles Police Department (LAPD) began an extensive investigation that produced over 150 suspects but yielded no arrests.

Short's unsolved murder and the details surrounding it have had a lasting cultural intrigue, generating various theories and public speculation. Her life and death have been the basis of numerous books and films, and her murder is frequently cited as one of the most famous unsolved murders in American history, as well as one of the oldest unsolved cases in Los Angeles County. It has likewise been credited by historians as one of the first major crimes in post–World War II America to capture national attention.