Sailors' superstitions

Sailors' superstitions have been superstitions particular to sailors or mariners, and which traditionally have been common around the world. Some of these beliefs are popular superstitions, while others are actually better described as traditions, stories, folklore, tropes, myths, or legend.

The origins of many of these superstitions are based in the inherent risks of sailing, and luck, either good or bad, as well as portents and omens that would be given associative meaning in relation to the life of a mariner, sailor, fisherman or a crew in general. Even into the 21st century, "fishers and related fishing workers" still have amongst the most dangerous jobs, with the second highest rate of mortality only after loggers.

By far the best known sailors' superstitions involve bad luck.

A "Jonah" is a long-established expression among sailors, meaning a person (either a sailor or a passenger) who is bad luck, which is based on the Biblical prophet Jonah. The comic character Jonah's name is a direct reference to the long established sailor's superstition. This concept is dominant in the film Master and Commander: The Far Side of the World.

Friday is considered to be an unlucky day in some cultures, and perhaps the most enduring sailing superstition is that it is unlucky to begin a voyage or 'set sail' on a Friday. However, this superstition is not universal. In the 19th century Admiral William Henry Smyth, writing in his nautical lexicon The Sailor's Word-Book, described Friday as

The Dies Infaustus, on which old seamen were desirous of not getting under weigh, as ill-omened.

(Dies Infaustus means "unlucky day".) This superstition is the root of the well-known urban legend of HMS Friday.

Sailors are often reluctant to set sail on Candlemas Day, believing that any voyage begun then will end in disaster. Thus may be related to the superstition to remove all Christmas decorations by Candlemas, a practice done well into Victorian times.

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