While many will laugh off the superstitious day, others will remain in bed paralyzed by fear and avoid daily tasks, conducting business or traveling. In the U.S., an estimated 17 to 21 million people suffer from a fear of Friday the 13th, according to a study by the North Carolina Stress Management Center and Phobia Institute.
The phobia, known as friggatriskaidekaphobia, is not uncommon. The word comes from “Frigga,” the name of the Norse goddess for whom “Friday” is named, and “triskaidekaphobia,” or fear of the number thirteen. It is also sometimes called “paraskevidekatriaphobia,” from the Greek “Paraskevi” for Friday, “Dekatreis” for thirteen and “phobia” for fear.
There will be three incidences of the superstitious day this year, Jan. 13, Apr. 13 and July 13. In the Gregorian calendar, Friday the 13th always occurs at least once a year and can appear up to three times in any one year.
The origin of fears surrounding Friday the 13th is unclear. There is reportedly no written evidence of Friday the 13th superstition before the 19th century, but superstitions surrounding the number 13 date back to at least 1700 BC.