Umibōzu (海坊主; Japanese pronunciation: [ɯ.mʲi.boꜜː.(d)zɯ, ɯꜜ.mʲi.boː-],[ lit. 'sea priest') is a giant, black, human-like being and is the figure of a yōkai from Japanese folklore.

Umibōzu (海坊主; Japanese pronunciation: [ɯ.mʲi.boꜜː.(d)zɯ, ɯꜜ.mʲi.boː-],[ lit. 'sea priest') is a giant, black, human-like being and is the figure of a yōkai from Japanese folklore. Other names include Umihōshi (海法師)[citation needed] or Uminyūdō (海入道)[citation needed]. Little is known of the origin of umibōzu but it is a mythical sea-spirit creature and as such has multiple sightings throughout Japan. Normally, umibōzu appears to sailors on calm seas which quickly turn tumultuous. It either breaks the ship on emergence or demands a bucket or barrel from the sailors and proceeds to drown them. The only safe way to escape an umibōzu is to give it a bottomless barrel and sail away while it is confused.