Abbreviation for "cashed bowl". Indicates that there is no more marijuana in the pipe, all that's left is ash.
Mike: "Damn dude, why'd you hand me a cb?"
Randy: "Well I got a hit..."
or
Randy: "That's a cb"
Mike: "Well load it again, dumbass, I'm not high yet"
Randy: "Well I got a hit..."
or
Randy: "That's a cb"
Mike: "Well load it again, dumbass, I'm not high yet"
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