The verb to haunt means to appear as a ghost or some kind of supernatural phenomenon. Ebenezer Scrooge was haunted by the Ghosts of Christmases Past, Present and Future.
The first recorded usage of the word haunt is in William Shakespeare’s A Midsummer Night’s Dream, a play filled with supernatural characters running around scaring the knickers off each other. As Shakespeare knew, haunting is at its most effective in the passive voice, because there is much more drama in being haunted than haunting. Another use of the word haunt is as a noun, and it means "a place that is frequented often," like a popular hangout. The gym, a bar, a corner: these are all potential haunts. The dentist, the principal’s office, a busy intersection: these are not.