Named after Ama-no-Murakumo-no-Tsurugi (天叢雲剣), or Sword of the Heavenly Gathering of Clouds, the legendary sword held by the Japanese Imperial Family as one of the three Imperial Regalia of the country. Its name was later changed to Kusanagi-no-Tsurugi (草薙剣), which means Grass-cutting Sword.