- FUN (Funafuti International Airport)
- FUNCPLAN (Functional Plan)
- Fund. (Fundatio ("Foundation"))
- FUNOPS (Functional Operational Testing)
- FUO (Foshan Airport)
- FUOR ((celestial object) FU Orionis objects, a class of variable pre-main sequence stars named after FU Orionis, the archetype for the class)
- FUOU (Festive Unusuals Owner Union)
- FUPAVEN (FUndacion PAnamericana VENezuela)
- FUPP-D (Full-Up Power Pack -Diagnostics)
- FUR (Future Utility Rotorcraft)
- FURPS (Functionality, Usability, Reliability, Performance, and Supportability)
- FUS (Franciscan University Of Steubenville)
- FUSA (Floresta, United States of America)
- FUSE ((telescope) Far Ultraviolet Spectroscopic Explorer, an ultraviolet space telescope)
- FUSS (Freshman Undergraduate Science Society)
- FUT (Pointe Vele Airport)
- FUTA (Federal University of Technology, Akure)
- FUTO (Federal University of Technology, Owerri)
- FUTS (Fight Until Safe)
- FUV (Fordham University's Voice)
- FUVITA ((instrumentation) Far UltraViolet Imaging Telescope Array, an ultraviolet imager for the Spectrum-Roentgen-Gamma mission)
- FV (fighting vehicle)
- FV/GCE (fighting vehicle gun control equipment)
- FVC (Fox Valley Conference)
- FVD (Foreign Voltage Detector)
- FVDD (Fighting Vehicle Development Division)
- FVE (Feature Vector Extractor)
- FVI (Friendship Village Information)
- FVL (Future of Vertical Lift)
- FVM (Fuvahmulah Airport)
- FVO (Female Voice Over)
- FVP (Front vertex power)
- FVPDS (Fielded Vehicle Performance Data System)
- FVPF (Family Violence Prevention Fund)
- FVR (Family Values Radio)