dumb as dirt
Severely lacking intelligence
Dumb as dirt describes someone profoundly stupid—so lacking in intelligence that they're compared to soil, which has no mind at all.
The phrase is folksy and dismissive: He's nice enough, but dumb as dirt.
Like similar expressions (dumb as a rock, dumb as a post), it emphasizes complete intellectual vacancy.
- idioticExtremely lacking intelligence
- stupidityLack of intelligence
- foolishLacking good sense
- brainlessDevoid of intelligence
- witlessLacking intelligence or sense
muttonheaded · ignorant · simpleminded · thick as a brick · cloddishness · unintelligent · blockhead · bumpkin · nincompoop · dullard · slow on the uptake · yokel · dim-witted · sharp as a marble · thick-headed · dunce · clueless · not the sharpest tool in the shed
dumb as dirtbrilliant
Intensely bright or gifted
genius · smart as a whip · sharp as a tack · brainy · intelligent
dumb as dirtworldly
Experienced in practical affairs
savvy · street-smart · shrewd · perceptive · sharp
dumb as dirtsharp as a tack
Extremely intelligent and alert
smart cookie · whiz · prodigy · mastermind · luminary
dumb, dirt, dumber, dumbest, dumbly, dumbness, dumbo, dirts, dirty