1. To go poop.
2. To have a large bowel movement, dropping the poop from your butt in a similar matter that a dump-truck would deposit a large load of waste.
1. I think I failed the test because the entire time I had to take a dump and the teacher would not let me get up from my seat. I could not concentrate.
2. I had to take a dump so bad that I left in the middle of the wedding ceremony.