Australia finally getting spinner on (4)
I believe the answer is:
atop
'on' is the definition.
(thesaurus)
'australia finally getting spinner' is the wordplay.
'finally' indicates one should take the final letters.
'getting' says to put letters next to each other.
'spinner' becomes 'top' (something that spins).
The last letter of 'australia' is 'a'.
'a'+'top'='ATOP'
(Other definitions for atop that I've seen before include "Situated on" , "Covering" , "highest level" , "On (poetic)" , "Surmounting" .)