1. an Australian island in the Indian Ocean, ab. 190 mi. (300 km) S of Java. 3300; 52 sq. mi. (135 sq. km).
2. one of the Line Islands, in Kiribati (Gilbert Islands), in the central Pacific; sovereignty disputed by U.S.: largest atoll in the Pacific; former U.S. test center for nuclear warheads. ab. 220 sq. mi. (575 sq. km).