Idzu
a province of Japan. It consists of a mountainous peninsula with numerous bays. It is 32 miles long and 16 miles wide. Its chief industries are the rearing of silk worms and the reeling of silk. It has several rivers, the most important of which is the Kanogawa.
The chief towns are Mishima and Shimoda.
IF (ef), a rocky island in the Gulf of Marseilles, crowned by a castle, the Château d'If, which was built by Francis I. of France, and subsequently used as a state prison. Here were confined, among others, Mirabeau and the Duke of Orleans (Philip Egalité), not to mention "Monte Cristo."
IFNI (if'nē), a small seaport in southern Morocco, 35 miles S. of Aguilon, ceded to Spain in 1883.