Definition

1. Noun:
   • A type of heat engine where the fuel is burned (combustion) within a sealed chamber inside the engine itself. This internal burning creates high-pressure hot gases that expand directly to produce mechanical work, typically by moving a piston or spinning a turbine.

Usage

• The internal-combustion engine revolutionized transportation in the 20th century.
• Most cars are powered by an internal-combustion engine that runs on gasoline or diesel.
• The efficiency of an internal-combustion engine is affected by its design and fuel type.

Advanced Usage

• Reciprocating internal-combustion engine: The most common type, where the expansion of gases drives a piston back and forth (reciprocates) in a cylinder.
  • The automobile's reciprocating internal-combustion engine converts linear piston motion into rotational motion at the crankshaft.
• Rotary internal-combustion engine: A type where combustion spins a triangular rotor within an oval chamber, instead of using pistons.
  • The Wankel engine is a famous example of a rotary internal-combustion engine.

Variants and Related Words

• ICE (n.): A common abbreviation for "internal-combustion engine."
  • Many governments are introducing policies to phase out new ICE vehicles.
• Engine (n.): A broader term for a machine that converts energy into motion. An internal-combustion engine is one specific kind.
• External-combustion engine (n.): A contrasting type of heat engine where fuel is burned outside the main engine unit to heat a separate working fluid (e.g., a steam engine).

Synonyms

• Heat engine: A more general term for any engine that converts heat energy into mechanical work.

Related Phrases

• Internal combustion: The process itself of burning fuel inside the engine.
  • The principle of internal combustion is central to the engine's operation.

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