1. The process of burning.
2. A chemical change, especially oxidation, accompanied by the production of heat and light.
3. Violent anger or agitation: Combustion within the populace slowly built up to the point of revolution.
[Middle English, from Late Latin combustiō, combustiōn-, from Latin combustus, past participle of combūrere, to burn up, blend of com-, intensive pref.; see COM- and ambūrere, to burn around (amb-, ambi-, ambi- + ūrere, to burn).]
com·bustive (-tĭv) adj.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.