boil over

boil over  {v. phr.}
1. To rise due to boiling and overflow down the sides of a pan or a pot.
"Watch out!" Jane cried. "The milk is boiling over on the stove!"
2. To become enraged to the point of being unable to contain oneself.
John took a lot of abuse from his boss, but after 25 minutes he suddenly boiled over and told him what he thought of him.
Categories: verb