A talent is wasted -- it's torture (9)
I believe the answer is:
tantalise
'torture' is the definition.
('torture'->'tantalize' is in my internal thesaurus and 'ize'->'ise')
'a talent is wasted' is the wordplay.
'wasted' indicates anagramming the letters.
'a'+'talent'+'is'='atalentis'
'atalentis' with letters rearranged gives 'TANTALISE'.
'it's' acts as a link.
(Other definitions for tantalise that I've seen before include "Tease, torment" , "Tease cruelly" , "Tease and entice" .)