an island of Italy, on the eastern side of the Bay of Naples, opposite to Ponte della Campanella. It consists of two lofty hills, with a fertile valley between them, which produces much wine and oil. The dwellings are scattered over the island, and the inhabitants amount to 3620. In ancient times it was the place of retreat of the Roman emperors. It is in longitude 14. 12. E. and in latitude 40. 32. N.