From The Jon Stewart Show, a description of particularly stupid people.

Not to be confused with "Potatoes with mouths."

Even better than "Potatoes with mouths" because potatoes can act as a conductor of electricity -- rocks just sit there.
Those people are so stupid, they are like rocks with mouths.
by D9 GM September 1, 2010
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A filthy braud who will take cock in the mouth in exchange for rock.
Hey man it's Jenny, ohhh wait here while i go to my car and get some rock. "Hey Jenny you rock mouth come blow me".
by MATTJ944 August 10, 2011
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