What does duh mean?
"Duh" is an informal interjection used to indicate that something is glaringly obvious, typically delivered in response to a question or remark whose answer should require no thought. Saying "Is the sky blue? Duh." signals impatience or amusement at a needless question. The word can also serve to caricature stupidity, mimicking the flat utterance of someone slow-witted. First recorded in American English in the twentieth century, it arose as an imitation of a dull vocalization rather than deriving from any older root. Though it carries a playful tone among friends, it can easily sound sarcastic, dismissive, or rude depending on delivery and context, which makes register awareness important. Despite its slangy origins, "duh" has been embraced by mainstream dictionaries and remains a vivid, economical way to punctuate the obvious.
interjectionUsed to express that something is obvious or self-evident, often in response to a statement or question whose answer should be apparent. It can also mockingly suggest that a person has just said or done something foolish.
- An interjection used to point out that something is obvious or self-evident, sometimes dismissively or sarcastically.
- An interjection mimicking stupidity or slowness of mind, used to portray or tease foolishness.
"“Did you know the store closes at nine?” “Duh — I work there.”"
"“Is water wet?” “Duh.”"
"When he finally found his keys in his own pocket, she just rolled her eyes and said, “Well, duh.”"
"Duh" began as an imitation of a dull-witted grunt and became so iconic that dictionaries now treat it as a legitimate English word.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of duh
"Duh" is an imitative or expressive formation, coined in American English during the twentieth century to mimic the sound of a dull-witted or dismissive utterance. It does not descend from Latin, Greek, or any other historical language, so it has no true cognates. Its spread was aided by American comedy and popular culture, and by the late twentieth century it had become firmly established enough in everyday speech to earn entries in major English dictionaries.
How duh is actually used
Highly informal and conversational; avoid in formal writing or professional speech. Tone matters greatly — it can be playful among friends but comes across as condescending or rude when said to strangers or in argument. More common in American English, though widely understood in British usage as well.
Easily confused with duh
"Duh" signals that something is obvious, while "d'oh" (popularized by The Simpsons) is an exclamation of frustration at one's own mistake.
"Duo" is a noun meaning a pair of people or things, whereas "duh" is an interjection commenting on the obviousness of something.