“Tora Tora Tora,” the message sent by Captain Mitsuo Fuchida, was the Japanese code expression for the signal to begin the attack on Pearl Harbor. “Tora” is a Japanese word that means “tiger,” but the entire phrase is considered an abbreviation for totsugeki raigeki, which implies “lightning attack.” These three simple words signaled that the December 7 attack was a surprise.

Source: Métraux, Daniel. “The Essentials: How the Film Tora! Tora! Tora! May Be Utilized as a Teaching Tool about Pearl Harbor.” Association for Asian Studies, Volume 26:2 (Fall 2021) Engaging Asia: Film, Documentaries, and Television, 2021, www.asianstudies.org/publications/eaa/archives/the-essentials-how-the-film-tora-tora-tora-may-be-utilized-as-a-teaching-tool-about-pearl-harbor/#:~:text=%E2%80%9CTora%20Tora%20Tora%E2%80%9D%20was%20the,which%20implies%20%E2%80%9Clightning%20attack.%E2%80%9D.