Medical

• FDI World Dental Federation
  FDI World Dental Federation
  The FDI World Dental Federation, established in Paris in 1900 as the Fédération dentaire internationale, is the world's leading organization representing the dental profession...
  
  , Fédération dentaire internationale. The World Dental Federation also have an Annual World Dental Congress, also known as the FDI.
• first dorsal interosseous
  Dorsal interossei of the hand
  The dorsal interossei of the hand are muscles that occupy the space between the metacarpals.-Structure:There are four dorsal interossei in each hand...
  
  , one of the four dorsal interossei muscles of the hand (not to be confused with the fourth dorsal interosseous)

Finance

• FDi magazine
  FDi magazine
  fDi Magazine is an English-language bi-monthly news and foreign direct investment publication owned by The Financial Times Ltd and edited in London. The A4 glossy pages reach a circulation of 14, 768 ABC “senior decision-makers involved in overseas investment” across the world...
  
  , a UK-based publication that covers foreign direct investment
• Federal Deposit Insurance Corporation
  Federal Deposit Insurance Corporation
  The Federal Deposit Insurance Corporation is a United States government corporation created by the Glass–Steagall Act of 1933. It provides deposit insurance, which guarantees the safety of deposits in member banks, currently up to $250,000 per depositor per bank. , the FDIC insures deposits at...
  
  , usually FDIC
• foreign direct investment
  Foreign direct investment
  Foreign direct investment or foreign investment refers to the net inflows of investment to acquire a lasting management interest in an enterprise operating in an economy other than that of the investor.. It is the sum of equity capital,other long-term capital, and short-term capital as shown in...
  
  , investment outside the economy of the investor
• Fraudulent Device Inhibitor, security to prevent skimming devices on automated teller machines
• Financial Derivative Instrument
  Derivative (finance)
  A derivative instrument is a contract between two parties that specifies conditions—in particular, dates and the resulting values of the underlying variables—under which payments, or payoffs, are to be made between the parties.Under U.S...
  
  

Computing

• Flexible Display Interface
  Flexible Display Interface
  FDI or Flexible Display Interface is an interconnect created by Intel in order to allow the communication of the HD Graphics integrated GPU found on supported CPUs with the PCH southbridge where display connectors are attached...
  
  , an interface to permit Intel CPUs with embedded graphics to communicate with compatible chipsets
• Formatted Disk Image
  Formatted Disk Image
  FDI is a file image of a disc created with the Disk2FDI PC software. It is often used to read Amiga or C64 discs and other discs formatted in a way that normally can't be read with a PC. The software uses two methods:...
  
  , a computer disc image format file

Other

• fault detection, in control engineering - dynamic system fault detection and isolation
• Formative Driven Instruction, an instructional model
• Foundation for Democracy in Iran
  Foundation for Democracy in Iran
  The Foundation for Democracy in Iran is a U.S. based Jewish organization. FDI was founded in 1995 by Kenneth R. Timmerman, Peter W. Rodman, Joshua Muravchik and zionist leaders advocating regime change in Iran....
  
  , US based Iranian dissident organization