clean as a whistle

(as) clean as a whistle

1. Neat and tidy in appearance. This house needs to be as clean as a whistle before my mother-in-law gets here.
2. Well-behaved and not involved in illegal or questionable activities. You can trust George, he's a good kid—as clean as a whistle. I don't have a criminal record, I'm clean as a whistle.
3. Entirely; totally. The handle just broke off, clean as a whistle! I can't believe it!
See also: clean, whistle
Farlex Dictionary of Idioms.

clean as a whistle

Completely, entirely, thoroughly, as in He chopped off the branch, clean as a whistle. The allusion in this simile is unclear. It may have been a replacement for the 18th-century clear as a whistle, which alluded to the pure, clean sound of a whistle (it has few overtones). However, it was adopted to describe something thoroughly done. [Early 1800s]
See also: clean, whistle
The American Heritage® Dictionary of Idioms by Christine Ammer.

clean as a whistle

1. If someone is as clean as a whistle, they have done nothing immoral or illegal. `There is no sex, drugs or rock 'n' roll. His private life is as clean as a whistle,' says McSmith. He emerged from this nasty, dishonest campaign with his reputation as clean as a whistle.
2. If something is as clean as a whistle, it is completely free from dirt. It leaves your face feeling clean as a whistle but not bone-dry.
See also: clean, whistle
Collins COBUILD Idioms Dictionary, 3rd ed.

clean as a whistle

1 extremely clean or clear. 2 free of incriminating evidence. informal
See also: clean, whistle
Farlex Partner Idioms Dictionary

(as) clean as a ˈwhistle

(informal)
1 (also (as) clean as a new ˈpin) very clean: She scrubbed the kitchen floor until it was clean as a whistle.
2 if somebody is as clean as a whistle, they are not involved in anything illegal: I don’t know why the police want to talk to me. I’m as clean as a whistle!
See also: clean, whistle
Farlex Partner Idioms Dictionary

clean as a whistle

Thoroughly or neatly done; also, pure, unsoiled. The early nineteenth-century use of this term, which appears in William Carr’s The Dialect of Craven (1828) as a proverbial simile meaning “wholly” or “entirely,” was in such guise as “Head taken off as clean as a whistle” (W. S. Mayo, Kaloolah, 1849). Why this should be analogous to a whistle is not certain. In the eighteenth century the simile was “clear as a whistle,” presumably referring to the pure sound produced by a whistle, relatively free of overtones. From “clear” and “pure” to “clean” is not so very far. Another theory holds that “whistle” came from “whittle”—that is, clean as wood is after being whittled—but this analogy seems less likely.
See also: clean, whistle
The Dictionary of Clichés by Christine Ammer
See also:
  • (as) clean as a whistle
  • be (as) clean as a whistle
  • (as) neat as a pin
  • neat
  • neat as a pin
  • poor but clean
  • clean up
  • in the hope that
  • neat as a new pin
  • clean as a new pin