int. and sb. [f. FIDDLE sb. or v., used in a contemptuous sense with a nonsensical appendage.]
A. int. Nonsense!
a. 1784. Johnson, in Boswells Life (1848), Appdx. 837/1. All he [Johnson] said was, Fiddle-de-dee, my dear.
1825. J. Neal, Brother Jonathan, I. 182. Fiddle de dee then; Ill venter it!
1865. Trollope, Belton Est., xxix. 352. He is a man very estimable,of estimable qualities. Fiddle-de-dee. He is an ape,a monkey to be carried on his mothers organ.
B. sb. Nonsense, absurdity.
Mod. That is all fiddle-de-dee.