Green’s Dictionary of Slang

f.u.j.i.a.m.a. phr.

[abbr.; note US milit. f.u.j.i.g.m.o., fuck you Jack, I got my orders]

written across an envelope back, fuck you Jack, I am all right, i.e. fuck you, Jack(, I’m all right!) under fuck you! excl.

[UK]Partridge DSUE (8th edn) 434/1: 1930s.