To not be in posession of something, usually refering to a dealer not having pot/drugs.
"yo, wut up nigga, u got what i need?"
"nahh man, i'm dry right now, but i should be good in a couple hours"
V. To deal or sell, most commonly, but not limited to drugs
(Most likely a derivative of the verb "slink")
"you still slankin' that shit?"