Onomatopoeia that evokes the musical flourish that accompanies dramatic climaxes in movies and theatre performances. Used to express an emotional reaction to a sudden change of circumstances or something brought up in conversation, usually surprise or trepidation.
Person A: "The boss wants me to run the department while he's away on holiday."
Person B: "Duh nah nah nah!"

Person A: "I have to get back for an exam tomorrow but they just cancelled my flight!"
Person B: "Duh nah nah nah!"
by ChenBL December 27, 2021
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