1. Fair dinkum. | An affirmation or response to good news.
This one of the most commonly used Australian expressions and one of the most difficult to define. The origins are said to have come from the gold-mining days when a Chinese miner was asked if he was finding a fair amount of gold. “Din-gum” meant “good gold.” Throughout time, this saying evolved into a positive response to good news. “Fair dinkum” can be used in a few different ways and it’s not always easy to know when to throw it into conversation.
It can be used to say that someone is genuine. “You can trust Jill, she’s fair dinkum.”
But it can also be used to ask if you’re telling the truth. “I just got a job in Africa!” “Fair dinkum?”