In technology:
* Application Development Framework: This is a common meaning in software development. It refers to a collection of tools and libraries that help developers build applications faster and more efficiently.
* Advanced Data Format: A file format used in video editing and other multimedia applications.
* Adobe Dreamweaver: A web design software program.
* Active Directory Federation Services: A service that allows users to access resources on different networks without having to log in to each one separately.
In other fields:
* Australian Defence Force: The armed forces of Australia.
* Australian Democrats: A former political party in Australia.
* Air Data Flow: Used in meteorology.
* Anti-Defamation League: A non-profit organization that fights anti-Semitism and other forms of bigotry.
* Aerodynamic Design Facility: A facility used to design aircraft.
To understand the meaning of ADF in a particular context, you'll need to consider the surrounding information. If you can provide more context, I can help you determine the specific meaning.