Sea Spright (also Sprite):
A ghost of the sea. The word usually refers to disembodied spirit, a ghost; a supernatural being, goblin or fairy. They haunt ships that have troubled pasts, such as mutinies or perhaps a ship that had a cruel master who was murdered or was beleived to be in league with the Devil. Some people consider former slaves ships to be haunted because of their past cargo. Some sprights haunt spots where ships had sunk, basically creating "haunted waters”. Occasionally a spright will bring warning of impending doom or warn sailors to stay out of the waters but most tend to be vengeful and or troublesome. The word spright dates back to the 1500s and is an alliteration of the word "spirit".
Pirates would often offer a blessing to men they marooned or tossed a man overboard in an effort to bring rest to the soul of the condemned. If the person's soul did not find rest, it was feared they would return from Davy Jones as a sea spright. This was a reason why some ships would not return to islands where men had been marooned or to waters where murderous mutinies occurred or men were thrown overboard.