boil over

present singular third person boils over · participle present boiling over · participle past boiled over · past boiled over

1. intransitiveTo boil to such an extent as to overflow its container.

   I forgot about the rice and it boiled over.

2. idiomaticintransitiveusuallyTo reach the point where aggressive action is taken.

   He b'iled right over, and the tongue-lashing he give that boss Right Liver beat anything I ever listened to. There was heap of Scriptur' language in it, and more brimstone than you'd find in a match factory.

   1913, Joseph C[rosby] Lincoln, chapter XIII, in Mr. Pratt’s Patients, New York, N.Y.; London: D[aniel] Appleton and Company, →OCLC

   1 more example

   But as the half progressed, Liverpool's pressure and high-tempo passing game increased United's frustration and it threatened to boil over on the stroke of half-time when Van Persie, who had already been booked, was involved in angry verbal exchanges with several Liverpool players, particularly Gerrard.

   2013 September 1, Phil McNulty, Liverpool 1-0 Man Utd, via BBC Sport

3. intransitiveTo act aggressively angry.

   He boiled over all night.

4. intransitiveTo buck aggressively.

   The stallion boiled over, throwing Robert from her back.