be dead and buried
From Longman Dictionary of Contemporary Englishbe dead and buriedbe dead and buriedUNIMPORTANTan argument, problem, plan etc that is dead and buried is not worth considering again The old argument about whether the UK should be a member of the EU should now be dead and buried. → deadExamples from the Corpusbe dead and buried• Gregory converted it too and Northampton knew they were dead and buried.• The defensive concepts of prewar days were dead and buried.