- FUED (First Unit Equipped Date)
- FUEL (Freedom Understanding Education And Life)
- FUG (Felderitц Usу Gépkosci)
- FUGAZI (acronym) (British/American Army slang, then Video Gamer FPS slang for Fucked Up, Got Ambushed, Zipped In.)
- FUI (File Update Information)
- FUIF (Fire Unit Integration Facility)
- FUIV (F*** You! I'm vested)
- FUIWSD (Fire Unit Integrated Weapon System Display)
- FUJ (Fukue Airport (Gotō Fukue Airport))
- Fujaba (From UML to Java And Back Again)
- FUJIGMO (Forget You Jack, I Got My Orders)
- FUK (Fukuoka Airport (Itazuke Air Base))
- ful (Fula language (ISO 639-2 code))
- FULDI (full diameter study report)
- FULT (Foundations of University Learning and Teaching)
- 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)