Large lanterns, usually of stone but also of metal, bamboo and other wood, which adorn shrine precincts. Also used for square (and chochin-shaped) paper lanterns used at festivals, principally o-bon, where toro are floated downriver to send away (okuribi) the souls of the ancestors. At the Miyazu-no-toro nagashi (the drifting lanterns at Miyazu, Kyoto) fireworks accompany a flotilla of 10,000 lanterns sent down the river on August 16th, while at the Omiya jinja, Kumamoto, each woman participant in a special kind of bon odori carries a lantern on her head.
A Popular Dictionary of Shinto. Brian Bocking.