To know someone in a deeper way, in the way a customer would know a drug dealer. This is not a person who you just say "what's up?" to, but who you know more personally, often knowing with certainty if said person is a drug dealer or not.

This is derived from the Chris Rock movie "Head of State"
I know him, but I don't _drug dealer know_ him
by Zodiac Digital September 26, 2005
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