To dream about a deer represents elegance, agility, and natural attractiveness. The feminine aspects of this creature could represent the feminine side of yourself. It also indicates sovereignty and strength. This dream could also be a play on words, such as someone who is 'dear' to you.
If you dream about a black deer, this could indicate that you need to pay more attention to the feminine traits within you. You should pay more attention to this aspect of you.
To dream that you kill a deer signifies that you are working to cover up those feminine aspects of yourself.