You get some number of points for guessing the true definition. You get a certain number of points for every time your daffynition is chosen by someone else. We total up the points at the end and the person getting the most points has the most points.

@jenny jenny: I'm afraid I'm going to have to say that if one of you votes for the other's daffynition nobody gets any points since I don't have any way to tell which of you submitted which daffynition. For a while I thought that it wouldn't make a difference but I'm not sure if that's the case. We'll see what happens if that scenario plays out.