a group of the Caroline Islands, in the N Pacific: part of the Federated States of Micronesia; an important Japanese naval base in World War II. 35,220; 50 sq. mi. (130 sq. km).
Chuuk (chŏŏk) An island group and state of the Federated States of Micronesia in the Caroline Islands of the western Pacific Ocean. Site of a major Japanese naval base during World War II, the islands were part of the U.S. Trust Territory of the Pacific Islands from 1947 to 1978.