A dove is thought of as being a pure creature and it is one that is thought of as consistently being a harbinger of good news. In this way, it is the opposite of a bird such as a raven or a vulture because it brings news of good tidings and of happy life. It carries a similar dream meaning too.
The dove and the olive branch is a popular symbol because of its biblical nature. The dove is known for being the first animal that Noah sent off of the ark to see if there was land that could be seen anywhere. The dove was of course unable to report back in speech but it was able to bring back an olive branch as a sign that plants were showing above the water and thus, land was available to spend time on. To have a dream about a dove then means that you feel adrift in life. There is something that you are holding out for and it just hasn't been coming to you. Never fear however, the dove is here to bring good news that if you hold out for just a little bit longer you will indeed be rewarded for your efforts and your patience.
The dove dream can also represent purity. You feel as though your life has been tainted somehow. Perhaps you have committed a crime which was against your own moral code and you feel bad about it. You may also have just done something that wronged another person and while it may not have affected you, you suddenly feel terrible for that person. The dove is a sign that you should receive retribution soon, or pursue it if you aren't already planning on it.