Namu Atoll (Marshallese: Nam̧o, [nʲæ͡ɑmˠɤ͡oo̯]) is a coral atoll of 54 islands in the Pacific Ocean, and forms a legislative district of the Ralik Chain of the Marshall Islands. Its total land area is only 6.27 square kilometres (2.42 sq mi), but that encloses a lagoon of 397 square kilometres (153 sq mi).