Many people have araskavedekatriaphobia (also known as friggatriskaidekaphobia), or fear of Friday the 13th.
Here are 13 facts about Friday the 13th:
- It's not clear where the superstition originates. Some believe it stems from the Biblical Last Supper, in which the unlucky 13th guest, Judas, betrays Jesus.
- Another Biblical belief is that Cain killed his brother, Abel, on Friday the 13th.
- Friday the 13th can come in threes - all years will have at least one Friday the 13th and as many as three Friday the 13ths in any given calendar year.
- More than 100 of the Knights Templar are also believed to have been tortured and later killed by King Philip IV of France on Friday, Oct. 13, 1307.
- If you have triskaidekaphobia, or fear of the number 13, you likely also have araskavedekatriaphobia — fear of Friday the 13th. Dr. Donald Dossey, a folklore historian, estimates that 17 to 21 million people suffer from triskaidekaphobia.
- Beloved rapper Tupac Shakur was killed on Friday, Sept. 13, 1996. Another notable Friday the 13th death was that of Julia Child in Aug. 2004.
- Some numerologists believe the number 13 is considered unlucky because of its relation to the number 12. Numerologists consider 12 a "complete" number: 12 months in a year, 12 apostles, 12 tribes of Israel, 12 labors of Hercules, 12 gods of Olympus, 12 hours on a clock.
- According to National Geographic, more than 80 percent of highrise buildings avoid having a 13th floor. Hospitals skip the 13th floor and many hotels skip having a room No. 13. Some airports even skip having a gate 13.
- The "Friday the 13th" movie franchise is going strong, despite many people's fears. Since the first film premiered in 1980, the franchise's 12 films have grossed more than $380 million at the box office worldwide, according to Box Office Mojo.
- Some symptoms of the phobia of the number 13 range from anxiety to all-out panic attacks. Many people will skip work on Friday the 13th.
- The number 13 is considered lucky by some. For pagans, it represents the number of full moons in a year.
- Historian and founder of the Stress Management Center and Phobia Institute in Asheville, North Carolina, Donald Dossey, told National Geographic, "It's been estimated that [U.S.] $800 or $900 million is lost in business on this day because people will not fly or do business they normally would do."
- Mary Kate and Ashley Olsen were born on Friday the 13th in 1986. Other celebs include Steve Buscemi, Julia Louis-Dreyfus, Kate Walsh and director Alfred Hitchcock. Perhaps that explains his obsession with psychological thrillers?
Editor's Note: This story was originally published on January 13, 2023.
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