For all of you vulgar people it can also mean the abbreviation for Unified National Fine (as in thread of a mechanical device that has a spiral groove cut in it for holding and fastening things together, most times called a "screw" that has no connotations to vulgarity.
When purchasing screws be sure to specify the thread type UNF as opposed to UNC
The University of No Football; Home of the Osprey; Also known as The University of North Florida. It is a relatively good school in Jacksonville, Florida that has NO FOOTBALL TEAM. Before attending this school students are blinded by the nice campus and good food so they don't realize there's NO FOOTBALL TEAM until it's too late.