internal combustion engine

engine which is powered by an explosion of fuel and air from within the engine

The internal combustion engine is an engine in which the combustion of fuel and an oxidizer (typically air) occurs in a confined space called a combustion chamber. This exothermic reaction creates gases at high temperature and pressure, which are permitted to expand. The defining feature of an internal combustion engine is that useful work is performed by the expanding hot gases acting directly to cause movement of solid parts of the engine, by acting on pistons, rotors, or even by pressing on and moving the entire engine itself.
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An engine in which the power is developed through the expansive force of fuel that is fired or discharged within a closed chamber or cylinder. (TRB1)

Noun
1. a heat engine in which combustion occurs inside the engine rather than in a separate furnace; heat expands a gas that either moves a piston or turns a gas turbine
(synonym) ICE
(hypernym) heat engine
(hyponym) diesel, diesel engine, diesel motor
(part-holonym) motorboat, powerboat
(part-meronym) engine block, cylinder block, block