In Japanese folklore, the baku is a yōkai known as a dream-eating supernatural creature.
People traditionally invoked the baku to consume bad dreams and protect sleepers. In older Japanese art and descriptions, it could appear as a composite animal with features associated with creatures such as an elephant, tiger, rhinoceros, bear, and ox. Its appearance has varied considerably across periods and sources.
The baku tradition entered Japan from Chinese mythology, where related dream-eating beings were known as mo. Over time, Japanese representations developed their own visual conventions and protective associations.
Modern popular culture frequently depicts the baku as a cute tapirlike animal. That image is connected with the Japanese word for the real-world Malayan tapir, but folklore descriptions are more fantastical. The baku is therefore not simply a zoological reference, and it is distinct from tsukumogami, spirits of transformed objects.