There are 2 results of your search for F.R.E.D..
F.R.E.D.
'flipping ridiculous eating device': Name given to the small eating implement that is found in most army ration packs. Most of the 'AJ's' (I use that nicely) use another well know swear word instead of 'flipping' though.
Contributor's comments: Anywhere there is an ARMY presence you will find the cruder variant of the above term in use.
Fred
Condom: She's pregnant!! Didn't you use a fred?