The most common and most likely answer to this crossword clue is the 9 letter word MONOTREME
I've seen this crossword clue in The Times
M
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More clues leading to the result MONOTREME
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The straight part
We know that "Aussie native" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case aussie native = monotreme.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does MONOTREME mean?
MONOTREME noun- A mammal that lays eggs and has a single urogenital and digestive orifice. Only the echidnas and platypuses are included in this group
- (of a pollen grain) Having a single trema, or aperture.