Almost always paired with the verb
打 (dǎ):
打零工 = 'to do odd jobs / gig work.'
零 here means 'scattered / piecemeal' (same
零 as in
零钱 'small change'), so
零工 is the opposite of
正式工作 'formal employment.' The modern 'gig economy' is often translated as
零工经济 (línggōng jīngjì).
