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spontaneous combustion

noun

the ignition of a substance or body from the rapid oxidation of its own constituents without heat from any external source.

Origin of spontaneous combustion

First recorded in 1800–10
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for spontaneous combustion

spontaneous combustion

noun

the ignition of a substance or body as a result of internal oxidation processes, without the application of an external source of heat, occurring in finely powdered ores, coal, straw, etc
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
spontaneous combustion in Science

spontaneous combustion

The bursting into flame of a mass of material as a result of chemical reactions within the substance, without the addition of heat from an external source. Oily rags and damp hay, for example, are subject to spontaneous combustion.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
spontaneous combustion in Culture

spontaneous combustion

A process by which a collection of materials (such as oily rags) catches fire without the application of heat from outside. The oxidation of substances in the materials starts the fire.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.