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external-combustion

American  
[ik-stur-nl-kuhm-buhs-chuhn] / ɪkˈstɜr nl kəmˈbʌs tʃən /

adjective

  1. noting or pertaining to an engine, as a steam engine, in which fuel ignition takes place outside the cylinder, turbine, or the like, in which heat energy is transformed into mechanical force.

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.