caloundra

As an adjective australia

is australian.

As a noun australia

is australian.

As a proper noun caloundra is

the southern-most community on the sunshine coast in south east queensland, australia.

As proper nouns the difference between queensland and caloundra

is that queensland is one of the six states of australia, occupying the north-eastern part of the continent, with its capital at brisbane while caloundra is the southern-most community on the sunshine coast in south east queensland, australia.