clean as a whistle
Proposed by a contributor, not yet supported by evidence.
Meaning · English
Completely clean or pure
Literally: free from dirt or impurities like a whistle
Where it’s used:
Used
Widespread English
Examples
A steep, wall as clean as a whistle, without a scrap of vegetation.
Recording quality (typical of JMT) is excellent — dynamic and clean as a whistle.
British National Corpus sentence via the MAGPIE corpus (CC BY 4.0, retrieved 2026-07-30)
Sources & notes
Listed in Wiktionary’s “English idioms” category (retrieved 2026-07-29); definition pending editorial review. Figurative class: Simile (PIE-English corpus, CC BY 4.0, retrieved 2026-07-31). Definition drafted by AI (@cf/meta/llama-3.3-70b-instruct-fp8-fast) and auto-approved by rule on 2026-07-30; pending editor spot-check.
Common questions
What does “clean as a whistle” mean?
Completely clean or pure Literally: free from dirt or impurities like a whistle
Is “clean as a whistle” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.