flashover

noun

flash·​over ˈflash-ˌō-vər How to pronounce flashover (audio)
1
: an abnormal electrical discharge (as through the air to the ground from a high potential source or between two conducting portions of a structure)
2
: the sudden spread of flame over an area when it becomes heated to the flash point

Examples of flashover in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Fire officials said there was a flashover on the second floor. — Jeramie Bizzle, CBS News, 20 Jan. 2026 Less than 90 seconds after the plane doors opened, the influx of oxygen feeding the fire caused a flashover. — Jeff Suess, Cincinnati Enquirer, 22 Mar. 2026 Medical staff said Friday that some of those in hospital appear to have injuries consistent with a flashover. — Billy Stockwell, CNN Money, 2 Jan. 2026 That fire began when indoor pyrotechnics ignited combustible materials on the walls and ceiling, leading to rapid fire spread and flashover conditions. — Christina Diaz, The Orlando Sentinel, 9 Jan. 2026 See All Example Sentences for flashover

Word History

Etymology

derivative of to flash over "to form such an electrical discharge"

First Known Use

1892, in the meaning defined at sense 1

Time Traveler
The first known use of flashover was in 1892

Rhymes for flashover

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Browse Nearby Words

flasholder
flashover
flashover voltage
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Cite this Entry

“Flashover.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flashover. Accessed 8 Jul. 2026.

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