When you are sitting on the toilet and someone comes up and flushes it before you are done pooping. You then can feel a moist breeze on your nuts.
Everything was coming out just fine until she sneaked up and gave me a Tropic Thunder from Down Under. I was unable to get off the toilet since I was not finished dropping my load. The cool breeze did feel nice on my balls though.
Nickname given to bales of marijuana thrown overboard or out of airplanes. Origin is reportedly from members of the US Coast Guard in the area of Southern Florida.
"Base we've got some square groupers floating outside of Miami harbor."