keep watch . keep watch {v. phr.} To be vigilant; be alert; guard. The police have asked the neighborhood to keep watch against an escaped convict. Categories: add yours {v. phr.} Source: A Dictionary of American Idioms by A. Makkai, M.T. Boatner, J.E. Gates © 2024 To section: K Subscribe to: American IdiomsIdioms feedEnglish languageHome page and general feed Discuss