We don't have synonyms for donative yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are native, donate and donation.
(n) :
(ecclesiastical law) A benefice conferred on a person by the founder or patron, without either presentation or institution by the ordinary, or induction by his orders.
(n) :
(ecclesiastical law) A benefice conferred on a person by the founder or patron, without either presentation or institution by the ordinary, or induction by his orders.