sea monster

Noun

sea monster (plural sea monsters)

1. A large and aggressive creature of the sea that attacks ships.
   • When there he was drawn down as before to the palace, but the fairy now was changed, and saying, "You have betrayed me - you shall die," she caused him to be devoured by the sea-monsters.1850, Thomas Keightley, The Fairy Mythology, London: H.G. Bohn, page 470
   • “However it occurred, my sword had killed
     nine sea-monsters.”1999, Seamus Heaney, Beowulf, London: Faber and Faber, page 20

   Synonyms:

   mermonster

2. Any huge marine animal.