1 C1 formal
(Firefighting/technical) For a fire to reach the stage where all combustible materials in an enclosed space ignite simultaneously.
"The investigators believe the blaze flashed over within seconds of the initial ignition."
flash over
C1 formal intransitive
For a fire to suddenly and simultaneously ignite all combustible materials in a space, causing an explosive spread of flames.
In plain English
When a fire suddenly explodes and fills an entire room with flames all at once.
What does "flash over" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 C1 formal
(Electrical) For electricity to jump across a gap or insulator, creating an arc.
"The power surge caused the current to flash over the insulator."
Literal vs figurative
Words literally mean
A flash (sudden, rapid light/flame) that goes over — covering an entire area at once.
Actually means
When a fire suddenly explodes and fills an entire room with flames all at once.
Usage tip
Primarily a technical firefighting and engineering term. The noun 'flashover' is the standard form. Rarely used outside emergency services, fire safety, and technical reporting contexts. ESL learners are most likely to encounter this in technical or news texts about fires.
Words that pair with "flash over"
Natural word combinations native speakers use most often.
fire room building point temperature stage
How to conjugate "flash over"
The five tense forms you'll use most often.
Base
flash over
I/you/we/they
3rd person
flashes over
he/she/it
Past simple
flashed over
yesterday
Past participle
flashed over
have + pp
-ing form
flashing over
continuous
Hear "flash over" in the wild
Listen to native speakers using "flash over" in real YouTube videos — click a clip to watch it on Looplines.
Other ways to say "flash over"
Swap in when you want variety — tap a linked one to explore it.
engulf explode ignite simultaneously
Keep exploring
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