Definition of "Sanya"

About forty bombers and fighters were based at the Hoihow Airport and at Sanya in the southern part of the island, both fields built by the Japanese and used in the war to strike at Allied positions in China and Southeast Asia.[...]CAT kept planes at its main base at Sanya on a standby basis for emergency evacuation in case of Communist invasion.

1972, Seymour Topping, “Departure”, in Journey Between Two Chinas‎, Harper & Row, pages 102–103

In mid-November, the commander of the Hainan Military Sub-district ordered troops stationed at Sanya Bay to join the demonstration.

1983 March 20, “Hainan protest over Teng's economic plans”, in Free China Weekly‎, volume XXIV, number 11, Taipei, page 3

One sample question: How will Chinese ballistic-missile submarines (SSBNs) based at Sanya, on Hainan Island, reach patrol grounds in the western Pacific should Beijing choose to send them out? To maintain stealth, SSBNs would first have to evade any adversary picket submarines lying offshore. Once in deep water, they would cruise eastward toward the Philippines. In all likelihood Chinese boats would exit through the Luzon Strait, the narrow sea between Taiwan and the Philippine island of Luzon.

2014, James R. Holmes, “Strategic Features of the South China Sea”, in Naval War College Review‎, volume 67, number 2, page 45

The aircraft can fly to the southernmost edge of China's territorial claims -- the James Shoal -- in just four hours from the southern city of Sanya, state-owned Global Times reported.

2017 December 24, “World's largest amphibious aircraft takes off in China”, in France 24‎, archived from the original on 24 December 2017