A narrow notch, groove or opening, as in a keyway in machinery or a slit for a coin in a vending machine. Also: a position in a group, sequence or series. From the Merriam-Webster Online Dictionary.
Slot is an open-source framework for developing video games that supports rapid development and deployment of graphical user interfaces (GUIs). The main advantage of slot over other frameworks is the fact that it enables developers to define both GUI elements and their functionality in separate components called slots. The slots are then connected by signals or events using the corresponding SLOT() and SIGNAL() macros. This allows a developer to write both a GUI and the core of the game in different languages, thus facilitating code reuse. This is especially beneficial when working on a complex and large project.