Tortured person first to divulge answer (7)
I believe the answer is:
respond
'answer' is the definition.
('respond' can be a synonym of 'answer')
'tortured person first to divulge' is the wordplay.
'tortured' indicates anagramming the letters (I've seen this in other clues).
'first to' says to take the initial letters.
The initial letter of 'divulge' is 'd'.
'person' is an anagram of 'respon'.
'respon'+'d'='RESPOND'
(Other definitions for respond that I've seen before include "Reply - react" , "Answer back" , "Come back" , "Write back" , "State in reply" .)