hōnō-zumō 奉納相撲

Hōnō-zumō is sumo performed at a shrine as an offering. That's how sumo began: early bouts were offerings to the gods, with prayers for a good harvest. Shrine events still happen, such as a yokozuna ring-entering ceremony at Tokyo's Meiji Shrine as part of the New Year celebrations.

We haven't yet checked this kanji against the Japan Sumo Association's own pages.