not (just) whistling Dixie

not (just) whistling Dixie

slang Having a realistic or honest view of something, as opposed to an overly optimistic one. "Dixie" was a song popular among Confederate soldiers during the US Civil War and became associated with continuing to hope for the success of a lost cause. It sounds like they really are going to give everyone a raise. You weren't just whistling Dixie, Bob!
See also: Dixie, not, whistle
Farlex Dictionary of Idioms.

not just whistling Dixie

Rur. not talking nonsense. (Alludes to a song titled "Dixie.") Man, you are right! You're not just whistling Dixie. When you say she is wrong, you're not just whistling Dixie.
See also: Dixie, just, not, whistle
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

not just whistling Dixie

(...ˈdɪksi)
tv. not talking nonsense. (Folksy. Refers to a song titled Dixie.) Man, you are right! You’re not just whistling Dixie.
See also: Dixie, just, not, whistle
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • not just whistling Dixie
  • be not whistling Dixie
  • Dixie
  • not be whistling Dixie
  • be whistling Dixie
  • whistle Dixie
  • whistlin
  • you ain't (just) whistling Dixie
  • You ain't just whistlin' Dixie
  • a lonely little petunia in an onion patch