engine

American  

[en-juhn] / ˈɛn dʒən /

noun

1. a machine for converting thermal energy into mechanical energy or power to produce force and motion.

2. a railroad locomotive.

3. a fire engine.

4. Computers. a piece or collection of software that drives a later process (used in combination, as in ).

5. any mechanical contrivance.

6. a machine or instrument used in warfare, as a battering ram, catapult, or piece of artillery.

7. a means by which something is achieved, accomplished, or furthered.

   Trade is an engine of growth that creates jobs, reduces poverty, and increases economic opportunity.

8. Obsolete. an instrument of torture, especially the rack.

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engine British  

/ ˈɛndʒɪn /

noun

1. any machine designed to convert energy, esp heat energy, into mechanical work

   a steam engine

   a petrol engine

2. 1. a railway locomotive

   2. ( as modifier )

      the engine cab

3. military any of various pieces of equipment formerly used in warfare, such as a battering ram or gun

4. obsolete any instrument or device

   engines of torture

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engine Scientific  

/ ĕn′jĭn /

1. A machine that turns energy into mechanical force or motion, especially one that gets its energy from a source of heat, such as the burning of a fuel. The efficiency of an engine is the ratio between the kinetic energy produced by the machine and the energy needed to produce it.

2. See more at internal-combustion engine steam engine See also motor

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Other Word Forms

• engineless
  adjective
• multiengine
  noun

Etymology

Origin of engine

First recorded in 1250–1300; Middle English engin, from Anglo-French, Old French engign, enging, from Latin ingenium “nature, innate quality, mental power, clever invention,” equivalent to in- “in” + -genium (equivalent to gen- “begetting” + -ium noun suffix); see in- ², kin, -ium

Explanation

An engine is a machine that burns fuel to make something move. The engine in a car is the motor that makes it go. Engines power vehicles including cars, trains, airplanes, and boats. While these engines tend to be powered by fuel that's burned, other engines get their power from electricity, which they convert to mechanical energy — fans, power tools, and small appliances all commonly have electric engines. Figuratively, you can also use the word engine to mean "something that's used to bring about a specific result." In your state, for example, tourism might be the main engine of job growth.

Example Sentences

KBR is in the midst of splitting its businesses; Engine thinks that is unnecessary.

From The Wall Street Journal • Apr. 30, 2026

Its 3D creation tool, the Unreal Engine, has been used to produce visual effects and virtual worlds for shows including Walt Disney Co. and Lucasfilm’s “The Mandalorian” and HBO’s “Westworld.”

From Los Angeles Times • Mar. 24, 2026

Under the multiyear partnership, which the companies announced Friday, AWS will use Cerebras’s chip, called the Wafer-Scale Engine, to help power so-called inference functions, which allow AI models to respond to user queries.

From The Wall Street Journal • Mar. 13, 2026

In December, Engine Capital published an open letter urging UniFirst to form a special committee of independent directors and “initiate a thorough assessment of value-maximizing alternatives.”

From Barron's • Mar. 11, 2026

Near the corner of Sixty-third and Wentworth, he passed a fire station that housed Engine Company no.

From "The Devil in the White City" by Erik Larson

Related Words

• appliance
• diesel
• generator
• instrument
• motor
• power plant
• tool
• transformer
• turbine
• weapon