The USS Nereus (AS-16) was a submarine tender of the United States Navy, launched on 24 March 1944. Designed to support submarines, it provided maintenance, repair, and logistical support. The ship was named after the Greek sea god, Nereus, and served primarily in the Pacific Theater during World War II. After the war, the USS Nereus continued to operate, supporting various submarine fleets until it was decommissioned in 1991. The ship played a crucial role in enhancing the operational capabilities of submarines, including those like the USS Nautilus and USS Dolphin, throughout its service life.