keen about . keen about or keen on {adj. phr.} Very enthusiastic about someone or something. It is well known that Queen Elizabeth is keen on horses. Categories: add yours {adj. 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 Read comments Discuss