Australia

Definition:
Good health.

Usage:
When someone sneezes, someone nearby may say gesundheit. It's the German equivalent of saying 'bless you.'

Definition:
Kitbashing is the art of building a scale model by adapting parts from another model kit

Usage:
"Nobody makes one quite like it, so I kitbashed this."

Definition:
Extremely tired, lethargic, rooted (see rooted), partied-out, faarked.

Usage:
They were too munted to leave the house, "I'm so munted im gunna sleep here in the gravel."
One can also have the munts.

Definition:
The name of the strip of grass between the sidewalk (the paved strip for people to walk on) and the street (where motorized vehicles run).
Update : In Australia it's called a Nature Strip.

Usage:
He mowed the lawn but forgot to do the devil's strip.

Definition:
1. To take off, to leave quickly
2. To be really good at something

Usage:
1. I'm late - I gotta jet...
2. Ask her. She's a jet at maths.

Definition:
A warning of something about to happen.

Usage:
Here is a heads up of this meeting this afternoon