What is a games engine

[Mariotroid]

I think it depends on the context.

For video games, I think the engine is how the code is set up to make the gameplay mechanics. For example, Mario jumping is a gameplay mechanic, but how fast he jumps, how high he jumps, and the direction he jumps in, are all engine related.

What about all the other mechanics like level mechanics? Is that what you need before you have an "engine"?