Baku ("dream eaters") are spirits found in Japanese mythology. They are generally pictured as composite creatures , either with the head of an elephant and the body of a lion or with the head of a lion, the body of a horse, the tail of a cow, and the legs and feet of a tiger. Alternatively, they may be more pig- or tapir-like creatures that range in color from black to pink.

Baku are generally benign creatures who aid human beings by eating nightmares or the evil spirits that cause such dreams. Sometimes they do this unbidden, but other legends require a nightmare sufferer to awaken and call upon a baku to eat his dreams. According to some beliefs, baku can change eaten dreams to good luck. Other tales make the baku more troublesome, eating all dreams and thus depriving sleepers of their beneficial effects, or simply awakening sleepers and depriving them of sleep in general.

Baku are almost always seen as beneficial, however, and pictures of the creatures are often placed in Japanese bedrooms to help ward off bad dreams (in modern times, baku toys and plush dolls may be used instead). In addition, people sometimes write the Chinese character for "baku" (獏) on pillowcases. In Edo-era, pillows with a baku depiction was sold widely.

The Pokémon Drowzee, a tapir-like creature that eats dreams, is obviously based on the baku.

See also: dreamcatcher (Native American)