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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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of flashover

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Phil's account suggests others in the crowd may have reacted only when the sudden and devastating flashover happened.

From BBC Jan. 17, 2026

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

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

The CFD, according to a report on the incident from Chicago's Fox 32 News, said the injuries were caused by a flashover at the fire.

From Fox News Feb. 12, 2022

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

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