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

There’s no denying that rhetoric over the bear hunt, which was approved by the state Fish and Wildlife Conservation Commission last summer, boiled over. — Orlando Sentinel Editorial Board, The Orlando Sentinel, 3 Aug. 2026

Tensions between Saudi Arabia and the Houthis in Yemen boiled over in July, threatening the March 2022 ceasefire. — Paul Iddon, Forbes.com, 1 Aug. 2026

The border crisis boiled over Thursday and continued Friday with security forces clashing with migrants on the Moroccan side of the border. — Yuliya Talmazan, NBC news, 31 July 2026

The announcement came after local authorities in Ceuta had asked the central government in Madrid for reinforcements to manage a border crisis that boiled over Thursday with large crowds of people breaching the border fence. — ABC News, 30 July 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