1) The last hit of cannabis in the one hitter. It’s not really a hit; it’s mostly ash.

2) Dirty ash at the end of a bong hit of weed.

3) The last remaining bit of very thin smoke after you’ve passed the pipe around the circle.
Dude! All you left me was the dirty caboose! Next time I want green!
by StonerCouple January 18, 2018
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