FU
FU is frequently used to mean follow‑up in medical notes, but it also appears in tech as file upload and colloquially to describe a foul‑up.
Medical
Miscellaneous
Frag University
Funny Uncle
Fertilizer Use
Fearless Unit
Fluorescence Unit
Funky Underpants
Future Unit
Formula Unit
Francis Urquhart
Freie Universität
Forever Unloved
Community
Governmental
Flight Unit
FUel
Farmacopea Ufficiale
Fart Underwater (submarine sound)
Fire Unit
First User
Food Unit
Foul Up
Academic & Science
Friends University
Forecast Unit
Fude University
Florida University
Fordham University
Frost Up
Furman University
Finite Union
Feedback Unit
Forces Unknown
Fraction Unbound