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.

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