Very small left-over particles of marijuana.

Grunyuns are created from the process of breaking down buds, rolling joints or blunts, or packing pipes & bongs.

The term shake is a comparable synonym.
"Dude don't throw that out! You know i save all the grunyuns!"

"If I want to smoke bad enough, I scrape together all the grunyuns I can find"

"Ehhh BOBO!! lemme get them grunyuns when you get done rolling that blunt!
by Sir Moose October 7, 2011
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The crumbs of chips and flavoring at the bottom of a bag of chips.
Hey man, you gonna eat those grunyuns?
by teaddub November 1, 2014
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