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1.
The most heavy and dense object known in existence.
Wow I got so hammered last night, this morning I could barely move I felt like a Jamaican Rock.

Guy- "Damn girl/guy you're making my dick is as hard as a Jamaican Rock right now."

Girl- "My nipples are as hard as a Jamaican Rock right now."
by dabestdocker July 11, 2011