to smoke a doobie means to smoke the leftover of a blunt. it's usually a small amount of greens left but anything's worth smoking when you're fresh out of weed, right?
JOHN: Max, you got some weed left from yesterday's burning session?

MAX: No..
wait, I do got a DOOBIE atleast.

JOHN: Ay That's good enough. We out to spark it, tho?

MAX: FASHOOOO!!!! We finna smoke a doobie
by The Crippled Stoner October 31, 2013
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