Definition of choom in English:

choom

noun

Australian, NZ
dated, informal
  • An English person.

    ‘there was the belief that the diggers were better fighters than the chooms’
    • ‘You said a choom put on your bandage.’
    • ‘The chooms should hand this criminal over, to face charges.’
    • ‘Thirty-one thousand people watched the Chooms roll over them in this match 33–10.’
    • ‘To the Australians these 'chooms' seemed naive, unworldly, and deferential.’
    • ‘There was the belief that the diggers were better fighters than the 'chooms'.’

Origin

First World War: representing a British English dialect pronunciation of chum.

Pronunciation

choom

/tʃʊm/