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.