In modern English, the term ghost ship has come to stand for at least one of three separate definitions, all of which involving unexplained circumstances. Historically, the term has been used to refer to reported sightings of apparitions over water that have appeared in the form of maritime sailing ships, often after having previously been known to have sunk, or to derelict vessels found floating with no crew. In fiction, ghost ships have often been vessels crewed by some manner of spectral beings.

Full Moons are traditionally associated with temporal insomnia, insanity and various magical phenomena such as lycanthropy. Psychologists, however, have found that there is no strong evidence for effects on human behavior around the time of a full moon. They find that studies are generally not consistent, with some showing a positive effect and others showing a negative effect (hence the terms lunacy and lunatic) Many neopagans hold a monthly ritual called an Esbat at each full moon, while some people practicing traditional Chinese religions prepare their ritual offerings to their ancestors and deities on every full and new moon