Some people make a distinction between 'just-in-time compilation' (like .NET - it's normal static compilation, but done just before first execution) and 'dynamic compilation' (like Java, it choses when to compile, uses dynamic information, may re-compile, etc.)
In the Julia community they frequently call it Just Ahead-Of-Time the compiler strategy of making the inference of all downstream types and methods to dispatch and compiling all at once. And the period while purely running a static program "world age", which usually lasts until you go back to the global namespace or you need any dynamic feature. Julia does not have an interpreter outside of the debugger.
