Evil in the sense of moral wickedness is often personified in dreams by the figure of the Devil - itself a corruption of Lucifer the light bearer. Evil is an expression of disapproval of that which cannot be explained away. Any violent action might be interpreted as evil - against the norm. Any darkness can also be seen as evil since for some time the colour black has been associated with it. To experience evil in a dream is usually to be conscious of our own urges, which we have judged to be wrong. Other aspects of evil, such as inappropriate action by others, may be experienced as dread and disgust. You might like to consult the entries for Dark/Darkness, Demon and Devil.