What is "alucarda"

Alucarda ( Spanish title: Alucarda, la hija de las tinieblas, or Alucarda, the daughter of darkness) is a 1978 Mexican horror film directed by Juan López Moctezuma, and starring Tina Romero in the title role. Often thought to be based on the 1872 novella Carmilla, it revolves around two teenage orphan girls living in a Catholic convent, who unleash a demonic force and become possessed by Satan. Though it is a Mexican Spanish language film, it was originally filmed in English, as evidenced by the fact that the lip movements match the dubbed English dialogue. It was released in theaters across Mexico on January 26, 1978.