1. To experience less success. That show was really popular when it first started, but it went off the boil in its later seasons.2. To become less pressing or urgent. During that crisis with our CEO, many other issues at the company just went off the boil.See also: boil, go, off
go off the boil
pass the stage at which interest, excitement, activity, etc. is at its greatest.See also: boil, go, off