One of the many words that Australians have cut syllables off and replaced with "-o". This one represents the hours after 12pm, and is used by people, myself included, who can't be bothered saying "-fternoon".
Hey Davo, I'm goin' to the servo for arvo smoko.

Translation: David, I'm going to the service station to purchase some food for the afternoon break.
by Choda Boy 57 September 8, 2006
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