Ambitious Parisian alto in action (12)
I believe the answer is:
aspirational
'ambitious' is the definition.
(ambitious might mean having aspirations)
'parisian alto in action' is the wordplay.
'in action' indicates anagramming the letters (I've seen this in other clues).
'parisian'+'alto'='parisianalto'
'parisianalto' is an anagram of 'ASPIRATIONAL'.
(Other definitions for aspirational that I've seen before include "After a role model" , "Characterised by hope or ambition" , "Pertaining to hopes" , "Like those trying to succeed" , "Characterised by a desire to be successful" .)