palace (n.) Look up palace at
early 13c., "official residence of an emperor, king, archbishop, etc.," from Old French palais "palace, court," from Medieval Latin palacium "a palace" (source of Spanish palacio, Italian palazzo), from Latin palatium "the Palatine hill," in plural, "a palace," from Mons Palatinus "the Palatine Hill," one of the seven hills of ancient Rome, where Augustus Caesar's house stood (the original "palace"), later the site of the splendid residence built by Nero. In English, the general sense of "splendid dwelling place" is from late 14c.

The hill name probably is ultimately from palus "stake," on the notion of "enclosure." Another guess is that it is from Etruscan and connected with Pales, supposed name of an Italic goddess of shepherds and cattle.