The Big Dictionary of Dreams

by Martha Clarke
When you dream that you killed someone, you are demonstrating a serious conflict between your aspirations and moral standards with which you are forced to comply. Such dreams must be analyzed very carefully because they indicate the need for deeper knowledge of the self before you reach a situation of real violence.

If in a dream you murder someone you know, you probably have a hidden resentment toward that person. On the other hand, the murdered person could also be a facet of yourself that you have been trying to suppress or destroy.

If the victim is yourself, perhaps you live subdued by your own emotions. The very same instincts that you refuse may be seeking revenge.

Some oracles believe this dream portends sadness. Notwithstanding, many others say that the act of killing someone in a dream surprisingly promises unexpected joy, recovery from of an illness, or a way out of an unfortunate period.

A Dictionary of Dream Symbols

by Eric Ackroyd
(1) Are your murdering someone? If the person is someone close, the dream may be expressing repressed hostility or resentment. There is often rivalry between siblings, or (unconscious) hostility towards a parent. Otherwise, what you are ‘murdering’ is probably some part of yourself (a repressed capacity or instinct or desire) that ought to be given a proper place in your conscious life.

(2) Are you being murdered? The murderer probably represents something in your unconscious: possibly a repressed emotion or instinct that is now threatening mutiny.

The Language of Dreams

by Patrica Telesco
(see Fighting, Weapons)

If the image is that of a young person, this represents having your goals or hopes figuratively “killed” before they could completely manifest.

Your own anger, hatred, fury, or prejudices revealing themselves through a heinous act.

This may be a circumstantial dream in which fears stemming from late night news manifest in the dream vision. Additionally, it may reflect your own abhorrence of such brutality.