The Tuni Nut is a quest item from The Legend of Zelda: Oracle of Ages. It is a mystical nut that maintains the balance of symmetry in Symmetry City, a small town in northern Labrynna. Veran attempts to destroy this city, one of the many deeds done to bringing forth an Age of Sorrow, by cracking the nut in the past.
Link discovers the city ruined in the present and travels to the past to collect the nut. He then takes it to an eccentric man named Patch to restore the nut to its former glory. Link restores symmetry by placing the nut on its pedestal, which is within a building in the northern center of town.
Just as Symmetry City is based completely around the idea of symmetry, the name "Tuni Nut" is a palindrome.