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

Bring to a boil over high heat, stirring. —Faye Levy, Oc Register, 3 Dec. 2025

Despite being tied for first place in the AFC North, frustration is starting to boil over in the Steel City following their 26-7 home loss to the Buffalo Bills on Sunday. —Cole Sullivan, MSNBC Newsweek, 3 Dec. 2025

Students and faculty concerns over the university's odd leadership change have simmered since the summer, but Jikeli's handling of academic freedom matters caused discontent to boil over. —Cate Charron, IndyStar, 1 Dec. 2025

Here in Washington, a simmering debate over immigration and national security has boiled over following the shooting of two National Guard members. —CBS News, 30 Nov. 2025

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