What exactly is a framework?

A software framework, in computer programming, is an abstraction in which common code providing generic functionality can be selectively overridden or specialized by user code providing specific functionality. Frameworks are a special case of software libraries in that they are reusable abstractions of code wrapped in a well-defined Application programming interface (API), yet they contain some key distinguishing features that separate them from normal libraries.

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System

If you don't know what it is, call it a system.

Module

If you don't know what it does, call it a module.

I don't know when to call a thing a framework though :-(