Referring to someone that has no intelligence. No common sense. Someone who is just dumb, as rocks have no intelligence.
Neil: Dude you gotta check out this new car I got!!
Bob: What kind of car did you get??
Neil: A black one, it's awesome.
Bob: (thinks to himself; "this dude is dumb as rocks.")
Bob: What kind of car did you get??
Neil: A black one, it's awesome.
Bob: (thinks to himself; "this dude is dumb as rocks.")
by cpetkunas June 30, 2020
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