Gym shoes / tennis shoes / sneakers.  Australians have a more beach-ified name for them!

This term is used a bit like bastard, to mean a disreputable person.  But if more Australians understood the origin of this term they might use it less often.

In Australia, the ground floor is counted as zero, the first floor is one storey up, and the second floor is two storeys up.  Americans would call it the third floor.

Used.  Pre-loved, pre-owned, handed down.  Like the English language which was bequeathed by the British to their ungrateful colony.

The main difference between Australian and American baking is that Australians don't use baking powder much.  They use self-raising flour, which is flour with baking powder already mixed in, as invented in Britain.  It is similar to American self-rising flour, but without the salt.  So when you see an Australian recipe calling for SR flour, make sure you add baking powder to your all-purpose flour (which, by the way, is called plain flour in Australia).

Napkin.  South Australians tend to refer to cloth napkins as serviettes and paper napkins as...paper napkins.

The upright crest (shag) on a cormorant (shag) brings readiness for this activity to mind.

Sheila was a common name for a woman in the early days of European settlement, being based on Sheilagh, an Irish name. Some people still call women sheilas or birds or chicks but these days if you want to refer to women casually you would probably just say girls.

It'll be all right.  Comes from She'll be nice, rhyming with Apples and spice, so She'll be apples.

Hair down there.

Treat.  To pay for someone else. "Whose shout is it?  Whose turn is it to pay?" "It's my shout."  From the old days when you shouted for service at a pub.

Smelled spelt (spelled) the British way.

Sausage.

Sorted out, organized, taken care of.

Tease; attempt to agitate someone.  "I was just stirring you."

A storey is a level in a building.  So a three-storey building will have a top floor which is a third floor in America but a second floor in Australia.

Exclamation of surprise, originating from God's truth!

Exclamation of emphasis.  Comes from May God strike me dead if I am lying.

Australian.  When read with an Australian accent, Strine sounds like Australian to us.  So... uh... I might have appropriated it for my pseudonym.

Erred.

Baffled, as if you have been plowing and have come up against an intractable object like a tree stump.

Superannuation, Australian retirement savings, equivalent to 401k plans in the US and private pensions in the UK. Australian employers are required by law to withhold super from employee wages and send it to their super fund.

A surgery is a doctor's office or clinic.

Originally, sweet as pie.  Now means awesome.