Iwojima, the famous patch of volcanic rock in the Pacific where Japanese and U.S. forces fought a fierce battle toward the end of World War II, is no longer known by that name, officially speaking.

The Geographical Survey Institute, which conducts surveys and provides basic geographic data for the nation, announced Monday that the official name of the island is now Iwoto, which is what local residents called it before the war.

Iwoto means "sulfur island." Since the Japanese word for island can be expressed as "shima" or "to," the meaning will stay exactly the same.

"Shima" and "jima" mean the same thing, but the pronunciation changes to "jima" depending on the character that precedes it.

The institute said the name was changed at the request of the island's former residents, who were displaced by the Self-Defense Forces.

Iwoto became widely known as Iwojima (sometimes spelled as two words) as U.S. military personnel spread its name far and wide for decades after the war. Some Japanese mainlanders use to call it Iwojima, too, spelling it that way on maps before World War II.

"I have felt something was wrong because the name of my hometown was called by a different name after the end of the war. I'm really happy," said 74-year-old Yoshiharu Okamoto, who heads an association of former Iwoto residents.

The island became the site of one of the fiercest battles of the war as 61,000 U.S. Marines landed to attack 21,000 entrenched Japanese soldiers in February 1945. In the end, all of the Japanese soldiers were killed or taken prisoner and about 29,000 marines were either killed or injured.

There were 1,164 Iwoto residents in 1944 before they were forced to evacuate.

Information from Kyodo added