Green’s Dictionary of Slang

(Aus.) irrelevance.

1961		Bulletin 17 May 38: ‘Squash, Rube, or bitter lemon?’ ‘Matter’f embuggurance, Vi.’.
1966		Baker Aus. Lang. (2nd edn).
1990		Australian 3 Mar. Weekend 16: The likes and dislikes of a Grub street penny-a-liner are a matter of profound imbuggerance to me and, I imagine, to most Australians.