Bushy tailed Aussie's post is interminable some say (6)
I believe the answer is:
possum
'bushy tailed aussie's post is interminable some say' is the definition.
I can't tell whether this defines the answer.
'post is interminable some say' is the wordplay.
'is interminable' means to remove the last letter (without the letter which terminates the word).
'say' indicates a 'sounds like' (homophone) clue.
'some' is a homophone of 'sum'.
'post' with its final letter removed is 'pos'.
'pos'+'sum'='POSSUM'
Can you help me to learn more?
(Other definitions for possum that I've seen before include "Small furry Australian marsupial" , "Play -- (pretend to be dead)" , "Small animal with a pouch" , "Australian marsupial with dense fur and a long tail" , "Dame Edna fan?" .)