IDF or idf may stand for: "idf" can be: short for "identifier" short for "identification" Acronyms Intel Developer Forum. Intermediate distribution frame (in Telephony and Computer networking) - a cable rack that interconnects and manages the telecommunications wiring between a main distribution frame (MDF) and workstation devices. Inverse Document Frequency, a factor in the tf–idf principle, used in Information Retrieval. Invention Disclosure Form, a precursor to filing a patent a… (More on Idf)