The 7th Antiaircraft Artillery Battalion (7th AAA Bn) was a United States Marine Corps antiaircraft unit that served during World War II. Formed in 1940 as the 7th Defense Battalion, its original mission was to provide air and coastal defense for advanced naval bases. It was one of first five defense battalions deployed in support of the color-coded war plans that called for the defense of Hawaii and other outlying United States possessions in the Pacific Ocean. These five battalions were nicknamed the "Rainbow Five." During the war the battalion defended Tutuila, Upolu, Savai'i and Nanumea and took part in combat operations at Anguar. The 7th was decommissioned before the end of World War II on 2 August 1945.