flashover

American  

[flash-oh-ver] / ˈflæʃˌoʊ vər /

noun

1. Electricity. a disruptive discharge around or over the surface of a solid or liquid insulator.

2. the moment of conflagration or complete incineration caused by superheated air or combustibles.

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verb (used without object)

1. Electricity. to have or experience a flashover.

flashover British  

/ ˈflæʃˌəʊvə /

noun

1. an electric discharge over or around the surface of an insulator

2. the sudden and rapid spread of fire through the air, caused by the ignition of smoke or fumes from surrounding objects

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Etymology

Origin of flashover

First recorded in 1890–95; originally noun use of verb phrase flash over

Example Sentences

The Crans-Montana fire bears the signature of flashover, the terrifying phenomenon by which a growing fire ignites much of a room nearby simultaneously.

From The Wall Street Journal • Jan. 4, 2026

In Friday's press conference, officials talked about a "flashover" happening in the bar.

From BBC • Jan. 2, 2026

Getting hotter, it soon reaches 1,128 degrees, and carbon monoxide in the smoke combusts — a flashover — propelling flames further.

From Los Angeles Times • Mar. 5, 2023

And the video footage appeared to show "flashover," when every combustible thing in an area is burning, he said.

From Fox News • Feb. 16, 2019

His research, looking at the impact of electrical current on sheep, is frequently credited with demonstrating how lightning’s flashover current can still inflict damage within the body.

From The Guardian • Jul. 13, 2017