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duh

American  
[duh, d] / dʌ, d /

interjection

  1. (used to express annoyance at banality, obviousness, or stupidity.)

duh British  
/ dɜː /

interjection

  1. slang an ironic response to a question or statement, implying that the speaker is stupid or that the reply is obvious

    how did you get in here? – through the door, duh
"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of duh

An Americanism dating back to 1960–65

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.