boil over

verb

boiled over; boiling over; boils over

intransitive verb

1

: to overflow while boiling

2

a

: to become violent or lose control because of anger

so frustrated he's ready to boil over

b

: to develop into something more violent

Their disagreement finally boiled over into a fight.

boilover

ˈbȯi(-ə)l-ˌō-vər 

noun

Examples of boil over in a Sentence

Recent Examples on the Web

And, in recent weeks, as tensions have boiled over in response to the killing of several people by ICE agents, thousands of people throughout the country — including Idahoans— have taken to the streets to protest the violent tactics used by immigration agents. —Alex Brizee, Idaho Statesman, 6 Feb. 2026

Anger is boiling over as utility customers in Indiana said their heating costs are getting out of control. —Sara MacHi, CBS News, 4 Feb. 2026

And there was some history that boiled over from the under-22 or under-23 series. —Sean Gregory, Time, 4 Feb. 2026

Frustration boiled over and a mass brawl broke out, culminating in Todibo’s dismissal after VAR officials advised referee Anthony Taylor to check the TV monitor. —Roshane Thomas, New York Times, 1 Feb. 2026

Word History

First Known Use

15th century, in the meaning defined at sense 1

Rhymes for boil over

• carryover
• changeover
• crossover
• cutover
• flashover
• hangover
• holdover
• layover
• leftover
• makeover
• moreover
• passover

Kids Definition

boil over

verb

1

: to overflow while boiling

2

: to become so angry as to lose one's temper