milk a duck

milking a duck

An impossible task. Used in comparisons to tasks or activities that are or seem to be impossible. Trying to get a straight answer out of this candidate is proving harder than milking a duck.
See also: duck, milk
Farlex Dictionary of Idioms.

milk a duck

tv. to do [or not do] something totally impossible. She can’t do that. That’s harder than milking a duck.
See also: duck, milk
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • milking a duck
  • be near to impossible
  • have no chance in hell
  • achieve the impossible
  • Catch-22
  • 22
  • a Catch 22
  • a catch-22 situation
  • a cold day in Hell
  • ain't it the truth