unregenerate in WordNet English dictionary

1. tenaciously unwilling or marked by tenacious unwillingness to yield
   stubborn  obstinate  unregenerate 
   
2. unrepentant and incapable of being reformed
   "an unregenerate criminal"
   unreformable  unregenerate 
   
3. not reformed morally or spiritually
   "unregenerate human nature"; "unregenerate conservatism"
   unregenerate  unregenerated