A isaster is the impact of a natural or human-made hazard that negatively affects society or environment. The root of the word disaster comes from astrology: this implies that when the stars are in a bad position a bad event will happen. The word derives from Middle French désastre, from Old Italian disastro, from the Greek pejorative prefix δυσ-, (dis-) "bad" + αστήρ (aster), "star".