When you dream knocking means: In your dreams, the meaning of knocking is different than it does in reality. It refers to the stage that transitions between sleep and wakefulness. It is a symbol of something happening or related to sleep paralysis. A dream about knocking out someone implies that you are expressing repressed feelings towards this individual. You might find the person that you want to knock out a target, or someone with unconscous characteristics similar to another. Direct anger can be expressed by knocking out someone’s teeth. Teeth are linked to the communication and speech that you are unhappy about. The idea of knocking someone out is a sign that you need to find balance and ground in your life.
(in Dream Dictionary)