The full form of FU is F**k You
One of the most commonly and frequently texted abbreviation that stands for ‘F**k You’. However you will find many who speak the letters ‘fu’ instead of actually cussing, especially if in the presence of children. The phrase ‘fu’ is known for being sailor language.

Origin of FU

When one curses too much using words like f**k it is known to be speaking like a sailor because they had the foulest mouths back in the early 1900s. Trying to prevent using the curse word women created the shortened version ‘fu’ to continue to speak and act like a lady without saying those words they were told only men spoke.