What does palātīnātus mean in Latin?

palātīnātus, a noun, means “palatinate”.

What is the genitive of palātīnātus?

The genitive singular is palātīnātūs. palātīnātus is masculine, fourth declension.

In classical Latin, [pa.ɫaː.tiːˈnaː.tʊs]; in ecclesiastical (church) Latin, [pa.la.tiˈnaː.tus].

noun · masculinefourth declension

palātīnātus m (genitive palātīnātūs)

Classical[pa.ɫaː.tiːˈnaː.tʊs]Ecclesiastical[pa.la.tiˈnaː.tus]

palatinate
Posteriate Lechi deficiente, Poloni comitiis Gnesnae de Repub.stabilienda habiis duodecim ex Procerum numero secundum totidem Palatinatus seu Provincias deligunt, quos Palatinos seu Woievodas, hoc est, duces belli lingua patria nominarunt, illisq; rerum summam committunt.Later, when Lech failed, the Poles, having held an assembly at Gnesna to establish a republic, elected twelve nobles from the same number of Palatinates or Provinces, whom they named Palatines or Voivodes, that is, war leaders in their native language, and entrusted the sum of their affairs to them.1626, Salomon Neugebauer, “Cracus.”, in Icones et vitae principum ac regum Poloniae omnium, page 3:
Duodenonageſimus Senator Laicus eſt Caſtellanus Praemetenſis, a Premecz, Palatinatus Poſnanienſis vrbe, denominatus.The eighty-eighth Lay Senator is Castellanus Praemestensis, named after Premecz, a town in the Palatinate of Poznan.1769, Historiarum Poloniae et Magni Ducatus Lithuaniae scriptorum quotquot ab initio Reipublicae Polonae ad nostra vsqve tempora extant omnium collectio magna […], Warsaw: Sumptibus typographiae Mizlerianae, page 242:

Proto-Indo-European *-tus Proto-Italic *-tus Latin -tus, -tūs Latin -ātus Latin palātīnātus From palātīnus + -ātus.