the shower that one takes in preparation for another shower. preformed when the party in question is so dirty that one shower would just not cut it. it is not uncommon to smell worse after a pre-shower, similar to the way dishes smell horrible right when they come out of the dishwasher.

When you eat dirt for the first time and leave your family to build a shack in the woods

The act of pleasuring ones self before a shower. A common act that has never really been given a term till now.

standing in the rain enough to get pretty wet. hence...a 'pre-shower'.