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fiddle-de-dee

American  
[fid-l-di-dee] / ˌfɪd l dɪˈdi /
Or fiddlededee,

interjection

  1. (used to express irritation, dismissive indifference, or scorn.)

fiddle-de-dee British  
/ ˌfɪdəldɪˈdiː /

interjection

  1. rare an exclamation of impatience, disbelief, or disagreement

"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 fiddle-de-dee

1775–85; fiddle + -de- (reduplication prefix) + (Tweedle)dee (in obsolete sense “fiddler”)

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.