duh

Duh is an informal interjection in the English language used to acknowledge that something should have been obvious. It expresses either a realization of something obvious or a mild mocking rebuke toward someone who failed to recognize it. In usage, it can serve as a standalone reply or be part of longer sentences, and is often conveyed with a playful or sarcastic tone in spoken language and online communication.

Etymology: The word is thought to be an onomatopoeic representation of a dull sound or a quick exclamation; its earliest published uses date from the mid-20th century in American English. It has since become a common part of casual speech, especially among younger speakers. The term is listed as an interjection in major dictionaries and appears in many media forms as a shorthand for obviousness.

Usage notes: Duh is generally appropriate in informal settings and among familiar interlocutors. It can come across as rude or dismissive in formal contexts or toward someone genuinely confused, so speakers should consider tone and audience. It is sometimes extended as phrases like “duh moment” to describe a moment of obvious realization.

In popular culture: Duh has been widely adopted in memes, cartoons, and social media, where short exclamations are used to punctuate punchlines. It appears in various comedic, editorial, and entertainment contexts as a shorthand for the obvious.