Weasel
To dream of a weasel represents a person or situation that you can't trust. Behavior that is sneaky, two-faced, or "bastardly." Someone that lies to your face or smiles at you before cheating you. It may also reflect a person that tells you whatever you want to hear to your face before cheating behind your back. Feeling stupid for having trusted someone.
Alternatively, it may reflect your own behavior that is deceitful to others. Awareness of yourself being a very ambitious dishonest person in some manner. Having no concern for others feelings at all if it means achieving a goal. No moral concerns about breaking promises.
Example: A man dreamed of a weasel biting his hand. In waking life he was fired. He felt a co-worker was in on it and worked to steal his job right out from underneath him.