Dreaming of a vicious dog signifies your inner conflict involving betrayal and lost of trust. When it barks, it could mean a response to unfriendly companions and surroundings. Learn to seek out the people or situation that tend to turn your stomach inside out and confront them, in order to pacify the vicious barking dog in you.
Vicious dogs in dreams also personify anger and rage against people who have hurt you emotionally in waking life – usually parents, ex-partners or bullies from childhood.
A vicious dog in a dream signifies uncontrolled emotions. They might also symbolize an aspect of ourselves that needs some attention to be dealt with in our waking life. If a person is feeling like they are constantly at the mercy of their emotions and that they have no control over them, then the vicious dog might represent this part of themselves in their sleep.