An azusa yumi (梓弓) is a sacred bow (yumi) used in certain Shinto rituals in Japan, as well as a Japanese musical bow, made from the wood of the Japanese azusa (梓) or Japanese cherry birch tree (Betula grossa). Playing an azusa yumi forms part of some Shinto rituals; in Japan, it is believed that merely the twanging of the bowstring will frighten ghosts and evil spirits away from a house. In Japanese poetry, the word azusa yumi functions as a makurakotoba ("pillow word", a kind of epithet).