A Titan out to win (6)
I believe the answer is:
attain
'win' is the definition.
(thesaurus)
'a titan out' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'titan' anagrammed gives 'ttain'.
'a'+'ttain'='ATTAIN'
'to' is the link.
(Other definitions for attain that I've seen before include "Reach, get there as with ambition" , "Achieve with effort" , "Gain with effort" , "Reach or achieve" , "Reach a goal" .)