come clean . come clean {v. phr.}, {slang} To tell all; tell the whole story; confess. The boy suspected of stealing the watch came clean after long questioning. Categories: add yours {slang} {v. phr.} Source: A Dictionary of American Idioms by A. Makkai, M.T. Boatner, J.E. Gates © 2024 To section: C Subscribe to: American IdiomsIdioms feedEnglish languageHome page and general feed Leave my opinion