What was the official Japanese document read in Hirohito's 1945 surrender broadcast called?

The official Japanese document read in Hirohito's 1945 surrender broadcast was the Imperial Rescript on the Termination of the War.

Hirohito's recorded address was the public reading of this imperial rescript, which instructed the Japanese government to accept the Potsdam Declaration. It was broadcast at noon on August 15, 1945, and became known as the Gyokuon-hōsō, or Jewel Voice Broadcast.

The rescript's language was formal and indirect. Rather than plainly saying “Japan has surrendered,” it referred to accepting the Allied terms and ending the war. Many listeners were unfamiliar with the courtly Classical Japanese style, and the poor sound quality of the recording made the message harder to understand.

The rescript should not be confused with the Japanese Instrument of Surrender. The rescript communicated the emperor's decision to the Japanese public; the instrument was the legal document signed by Japanese and Allied representatives aboard USS Missouri on September 2. Both were essential stages in Japan's surrender, but they served different purposes.