A marijuana addict, a stoner, a pothead. "Grass" is a well-known term for marijuana.
Curious George always wondered what the Man in the Yellow Hat has been smoking lately that smelled so good. And so George then sneaked into a weed cabinet which the Man in the Yellow Hat has left unattended, grabbed a few J's and a lighter and then started enjoying himself. He could not stop afterwards. What a grass monkey he now is!
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Mark H. Proud Urban Dictionary author since February 2004.
A ghetto drank. Made by filling a cup half full with Busch Light. Then you peel a fresh orange. Squeeze the orange into the drank. After the orange is fully squeezed pour the rest of the Busch Light into the cup. Drink the Grass Monkey.
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."