(Japanese mythology, mythology) A type of supernatural being said to devour nightmares.
2005, David Booth, Story Drama, 2nd edition, Pembroke Publishers, page 49,
The creature explained that he was a baku. A baku eats dreams and nightmares. To a baku, a bad dream is delicious!
2008, "Baku", entry in Brenda Rosen, The Mythical Creatures Bible, Octopus Publishing Group, page 113,
A person awakening from a nightmare should call three times saying, "Baku, eat my dreams." Thus summoned, the Baku will turn bad omens into good fortune by devouring evil influences.