make sit up . make sit up {v. phr.} To shock to attention; surprise; create keen interest. Her sudden appearance at the party and her amazingly low-cut dress made us all sit up. Categories: add yours {v. phr.} Source: A Dictionary of American Idioms by A. Makkai, M.T. Boatner, J.E. Gates © 2024 To section: M Subscribe to: American IdiomsIdioms feedEnglish languageHome page and general feed Add my comment