Aussie native's bill cut up (6)
I believe the answer is:
wombat
'aussie native's bill cut up' is the definition.
I can't tell whether this definition defines the answer.
'bill cut up' is the wordplay.
'bill' becomes 'tab' (a tab is a bill at a bar).
'cut' becomes 'mow' (as in mowing a lawn).
'up' says the letters should be written in reverse (in down clue: letters go upwards).
'tab'+'mow'='tabmow'
'tabmow' back-to-front is 'WOMBAT'.
Can you help me to learn more?
(Other definitions for wombat that I've seen before include "Burrowing animal" , "Australian burrowing marsupial" , "Tailless marsupial down under" , "Australian animal resembling small bear" , "Australian animal like small bear" .)