Green’s Dictionary of Slang

commo n.

[abbr. + -o sfx (3); note Aus. commie does not have the same political use as UK/US, but refers to those who live in rural communes]

[1940s+] (Aus.) a communist, or one whose views, from hard left to mildly liberal, are seen as deviant from the speaker’s (right-wing/conservative) ‘norm’; also as adj.