Top definition
1. An enormous, dense, tightly packed mass of poop capable of achieving mass destruction by means of toppling trees, buildings, and the American dream.

2. Big/big round poop.
1. Today at work I sit down, then I dropped a butt boulder in the trash can.

2. This is a heavy butt boulder, daddy, what did you eat?

3. Would someone please tell me what "butt boulder" means?

4. Do me in the butt, then eat my butt boulder.
by AdamWW December 16, 2005
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