taper down . taper down {adj. phr.} To decrease; reduce. He has tapered down his drinking from three martinis to one beer a day. Categories: add yours {adj. phr.} Source: A Dictionary of American Idioms by A. Makkai, M.T. Boatner, J.E. Gates © 2024 To section: T Subscribe to: American IdiomsIdioms feedEnglish languageHome page and general feed Leave my opinion