engine
The French word for 'engine' is 'moteur'. It is used in the context of a mechanical device or vehicle similar to its use in English. For example, 'moteur de voiture' is 'car engine'. Just like in English, it can also represent the driving force of something in a metaphorical sense.
The engine of my car is broken.
This sentence is expressing a problem with a car, specifically that the engine is not functioning properly or is 'broken'. In French, 'en panne' is used to express this.
The Google search engine is very popular.
In this statement, the speaker is commenting on the popularity of Google as a search engine - or, 'moteur de recherche' in French. It's used extensively worldwide for internet searches.
The windmill produces electricity thanks to an engine.
This sentence describes the function of a windmill, which is to generate electricity. The working mechanism behind this is the engine, or 'moteur' in French.