Father has part in release (6)
I believe the answer is:
parole
'release' is the definition.
(paroling is a kind of releasing)
'father has part' is the wordplay.
'father' becomes 'pa' (pa can mean dad or father).
'has' says to put letters next to each other.
'part' becomes 'role' (eg a theatrical role).
'pa'+'role'='PAROLE'
'in' is the link.
(Other definitions for parole that I've seen before include "Early release on promise of good behaviour" , "Give Al rope when he's released early" , "Temporary release (of a prisoner)" , "Conditional release from prison" , "Provisional release (for prisoner)" .)