This a word you hear. Or could hear from the Kiwis and the Ozzies. Peter brought it up, so I thought I would elucidate. It is definitely a derogatory word, and usually said with the F word in front of it. Do not use it. Bad manners. I suppose it reference the idea that some were not able to escape the culture or the influence.
OR maybe POME
'Prisoner of Mother England', slang term for British citizen.