I think I've pissed myself

POM-POMs

On his retirement as chief editor of the Oxford English Dictionary, John Simpson offered insight into the etymology of some English words and phrases. Including pom.

An enduring myth is that the word pom (as in whinging pom and other more colourful expressions) is an acronym from either "Prisoner of His Majesty" or even "Permit of Migration", for the original convicts or settlers who sailed from Britain to Australia.

John Simpson

Actually, I thought that it was an acronym for Prisoner of Mother England

We start with the word immigrant, well-established by the mid 19th Century as a settler. In a joking way people would play with immigrant from around 1850 or so, turning it into a proper name (Jimmy Grant), to give the strange immigrants a pseudo-personality. Equally playfully, a Jimmy Grant morphed around 1912 into pomegranate and immediately into pom, which it has stuck as till today.

John Simpson

Personally, I still prefer my version. But either way, as prisoner or immigrant the epithet hardly applies to an outsider to the Great Southern Land; surely, it's more relevant to the inhabitants of HMP Australia.