fall on . fall on or fall upon {v.} 1. To go and fight with; attack. The robbers fell on him from behind trees. 2. {formal} To meet (troubles). The famous poet fell upon unhappy days. Categories: add yours {formal} {v.} Source: A Dictionary of American Idioms by A. Makkai, M.T. Boatner, J.E. Gates © 2024 To section: F Subscribe to: American IdiomsIdioms feedEnglish languageHome page and general feed Add my comment