To dream of a comedian represents you or someone else that is making an effort to prove that everything happening in a situation is ridiculous. A carefree attitude or someone that is trying to encourage you to be carefree.
Alternatively, a comedian may reflect embarrassments or surprises that serve to relieve pressure or tension. A problem may be proving itself to be consistently over-hyped or ridiculous. A comedian may also be a sign that you are trying to laugh at yourself or not take a situation too seriously.
Negatively, may be a sign that you or someone else is too concerned with never being serious. Making light of everything to the point irritating other people, hurting others feelings, or not taking a dangerous situation seriously at all.
Example: A man dreamed of seeing the Chris Rock. In waking life his father was trying to sell a house for a price that he felt was ridiculously too high to ever have a serious buyer. The banks ended up rejecting every buyers offer just like he predicted. The Chris Rock reflected his perception of the banks rejections proving his belief that the asking price was ridiculous.