FD or similar may refer to:
Biology Familial dysautonomia, a disorder of the autonomic nervous system Ferredoxin, iron–sulfur proteins
Computing File descriptor, in Unix and related computer operating systems Freedesktop.org (fd.o), an interoperability project Functional dependency, a constraint in a relation from a database
Transportation
Automotive Mazda RX-7 (FD), a car Nissan FD engine, for trucks and buses Formula Drift, an American motorsport series
Aviation Thai AirAsia, IATA airline code FD FD Phantom, original name for the FH Phantom jet fighter Flight director (aeronautics), a flight instrument
Other modes of transportation Russian locomotive class FD Flying Dutchman (dinghy)
Business and politics Fixed deposit, a financial instrument Finance Director, or chief financial officer, in a company Financial Dynamics, a UK business services and lobbying firm acquired by FTI Consulting in 2006 Force of the Right (Forța Dreptei), a Romanian political party Fidei defensor (Latin, 'Defender of the Faith'), part of the full style of many English/British monarchs
Other uses Fire Department, providing firefighting services Canon FD lens mount, a standard for connecting a lens to a camera Fermi–Dirac statistics (F–D statistics), in quantum statistics
See also
Floppy disk drive (FDD) in early computers