Private First Class William Robert Caddy, (August 8, 1925 – March 3, 1945) was a United States Marine who sacrificed his life to save the lives of his platoon leader and platoon sergeant during the Battle of Iwo Jima. For his bravery, he posthumously received his nation's highest military decoration — the Medal of Honor. He was the 72nd Marine of World War II to receive this honor.