Everyone knows about Homicide (the killing of another human being), Suicide (the killing of oneself), and Regicide (the killing of a monarch). Here are some of the "Cides" you didn't hear about in your criminal justice class.
The killing of a person during an attempted rescue, unwittingly, by the rescuer.
The killing of a character from a work of fiction.
The removal of an existing person by the killing of ancestral bodies that would otherwise lead to that person's creation. Requiring time-travel, as popularized in James Cameron's Terminator series.
The killing of a man by a person who was present in his or her Mother's womb during her act of intercourse with the victim. Generally in reference to murders of vengeance wherein the victim is someone other than the killer's own father ( i.e. step-father, mother's boyfriend). Known in certain circles of the Italian Mafia as "Il Riturno Ultima", or "the Ultimate Comeback".