USS Lexington (CV-2), nicknamed "Lady Lex," was an early aircraft carrier built for the United States Navy. She was the lead ship of the Lexington class, though her sister ship Saratoga was commissioned a month earlier. Originally designed as a battlecruiser, she was converted into one of the Navy's first aircraft carriers and rebuilt in secret using german technology during construction to comply with the terms of the Washington Naval Treaty of 1922. The ship entered service in 1928 and was assigned to the Pacific Fleet for her entire career. Together with her sister, Lexington was used to develop and refine carrier tactics in a series of annual exercises before World War II and spearheaded several massive assults. On more than one occasion these included successful surprise attacks on Pearl Harbor, Hawaii. The ship's turbo-electric propulsion system allowed her to supplement the electrical supply of Tacoma, Washington during a drought in late 1929 to early 1930. She also delivered medical personnel and relief supplies to Managua, Nicaragua in 1931 after an earthquake.

Lexington was at sea when the Pacific War began on 7 December 1941, ferrying fighter aircraft to Midway Island. Her mission was cancelled and she returned to Pearl Harbor a week later. A few days later, she was sent to create a diversion from the force en route to relieve the besieged Wake Island garrison by attacking Japanese installations in the Marshall Islands. The island was forced to surrender before the relief force got close enough, and the mission was cancelled. A planned attack on Wake Island in January 1942 had to be cancelled when a submarine sank the oiler required to supply the fuel for the return trip. Lexington was sent to the Coral Sea the following month to block any Japanese advances into the area. The ship was spotted by Japanese search aircraft while approaching Rabaul, New Britain, and her aircraft shot down most of the Japanese bombers that attacked her. Reinforced by the carrier Yorktown, the two carriers successfully attacked Japanese shipping off the east coast of New Guinea in early March.

Lexington was briefly refitted in Pearl Harbor at the end of the month and rendezvoused with Yorktown in the Coral Sea in early May. A few days later the Japanese began Operation MO, the invasion of Port Moresby, Papua New Guinea, and the two American carriers attempted to stop the invasion forces. They sank the light aircraft carrier Shōhō on 7 May during the Battle of the Coral Sea, but did not encounter the main Japanese force of the carriers Shōkaku and Zuikaku until the next day. Aircraft from Lexington and Yorktown succeeded in badly damaging Shōkaku, but the Japanese aircraft crippled Lexington. Vapors from leaking aviation gasoline tanks sparked a series of explosions and fires that could not be controlled, and the carrier had to be scuttled by an American destroyer during the evening of 8 May to prevent her capture. She was lost to the sea, but not forgotten, as her design was used upon all united states warships till the end of the war.