There are many terrifying and determined horror movie villains. The ones that haunt our dreams and make us check for monsters under the bed are the best. They're the ones that creep up your spine and pour their evil over your already rising gooseflesh. They follow you home at night, when the family is out and the dog is at the vet. They watch from the trees, the fields, and the back seat of dilapidated cars. They're large, hulking, fast and crazed, which is what makes them so terrifying. They're also generally male.
Of the top grossing scary movies of all time, most of the villains are male, with the exception of The Exorcist and The Ring. Nonetheless, in The Exorcist, the actual villain is Pazuzu, the demon dwelling inside of Regan. Demons are genderless. As for the latter movie, a VCR can defeat Samara, so her badassness is in question.
However, there's no debate about the women on the following list. They are tough, powerful, intimidating, skilled in their area of death dealing and difficult to escape. Of course, they're also mean-tempered troublemakers, though that's really an understatement.