When a person gets so hot that a tiny sweat resevoir forms at the small of their back. Once it reaches full capacity it begins to trickle or flow down the natural crevice tween one's ham hocks (buttocks)
"Dude! I was so sweaty from rollerblading! Springtime came early and I had a buttcheek waterfall ... Yosemite-style-Yo!"
by mafabiotch November 29, 2011
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