A colorful comparative insult used to describe someone of spectacularly low intelligence.
A colorful comparative insult used to describe someone of spectacularly low intelligence. Like its cousin 'dumb as a box of rocks,' it leans on an inanimate object — the doorknob — as the benchmark of stupidity. The humor comes from the deadpan logic: a doorknob performs one simple function and has no inner life whatsoever. Calling someone dumb as a doorknob suggests they may not even clear that bar.
I tried explaining the refund process to him twice, but the guy was dumb as a doorknob and kept asking the same question.
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Regional slang from around the English-speaking world — British, Australian, Irish, Caribbean, Nigerian, Filipino, AAVE, and the hyphenated-English dialects that make the internet sound local.
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An American slang simile meaning extraordinarily stupid, describing someone whose intelligence is comparable to an inanimate collection of stones — which is to say, absent entirely. The image is deliberately absurdist and vivid: rocks have no intelligence at all, so being dumber than a box of them is a spectacular insult. Commonly heard in the American South and rural regions, it's colourful trash talk delivered with a straight face for maximum comedic effect.
(simile, slang) Very stupid.
(slang) Very stupid.
An American simile meaning spectacularly, almost impressively stupid. The comparison to dirt — the most ordinary, inert substance imaginable — underscores that the person being described has achieved a kind of peak dullness. Used affectionately among friends or as a pointed insult depending on tone, 'dumb as dirt' is a timeless piece of folksy American trash talk that's found its way into everyday conversation across the English-speaking world.
(simile, slang) Very stupid.
“I have never seen anyone lie so often about so many things. How can anyone believe anything he says? Does he really think the gop are behind him at this point? Seriously, you'd have to be as dumb as a doorknob not to see how throughly he's fucked everyone.”