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The residue in a bag of weed that, because of its size, has filtered through the larger buds to the bottom, getting to about the size of a crumb that would be stuck in a grandfather's beard.
Let's roll a joint, I've got a lot of grandfather crumbs.

What the fuck? When he chopped the weed he left me with all the grandfather crumbs. What an asshole!
by 1234509876 October 25, 2010
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