cost a bomb . cost a bomb or an arm and a leg {v. phr.} To be extremely expensive. My new house has cost us an arm and a leg and we're almost broke. Categories: add yours {v. phr.} Source: A Dictionary of American Idioms by A. Makkai, M.T. Boatner, J.E. Gates © 2024 » In RussianTo section: C Subscribe to: American IdiomsIdioms feedEnglish languageHome page and general feed Comment on this entry