wraith

An apparition of someone that is believed to appear as a portent just before that person’s death.

The ghost of a dead person.

Something faint or insubstantial.

An apparition in the exact likeness of a person, supposed to be seen before or soon after the person’s death; in general, a visible spirit; a specter; a ghost.

An apparition of a person in his exact likeness, seen before death, or a little after; hence, an apparition; a specter; a vision; an unreal image.

Sometimes, improperly, a spirit thought to preside over the waters; — called also water wraith.

A ghost or specter, especially seen just after a person’s death.

a mental representation of some haunting experience