The “final girl theory” is meant to describe the trope in horror films of one female character being the last to survive, having to defeat the killer, and live to tell the tale. While Carol J. Clover
originally coined the term in her 1987 essay Her Body, Himself: Gender in the Slasher Film and applied it mainly to American slasher films of the ’70s and ’80s, it’s still used in contemporary cinema in a variety of horror films to describe the surviving female character. As slasher films have seen a decline in popularity since their “golden age,” the use of the term “final girl” has expanded to include different sub-genres of horror films, as well as how the final girls themselves behave throughout the films.
The original meaning of the final girl, as described by Clover in 1987, defined the girl as the sole survivor of the group who has a final confrontation with the villain.