Imprisoning the aunt I caught, it's true (9)
I believe the answer is:
authentic
'true' is the definition.
(thesaurus)
'imprisoning the aunt i caught' is the wordplay.
'imprisoning' indicates putting letters inside.
'caught' becomes 'c' (cricket abbreviation).
'the' put inside 'aunt' is 'authent'.
'authent'+'i'+'c'='AUTHENTIC'
'it's' is the link.
(Other definitions for authentic that I've seen before include "24 [LEGIT]" , "Ian, the cut is genuine" , "Real, genuine" , "reliable" , "Genuine, not a copy" .)