A Columbian Doctor is an individual who leads the physical process of creating cocaine. A drug scientist.
Tyler: "Whoa dude, did you see the news last night? They busted up a huge cocaine ring down south and even caught a couple Columbian Doctors that were heading up the operations!"

Ben: "Wait, what?"

Tyler: "Drug scientists, you know, right?"
by TRPooper September 2, 2011
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