The fear of Friday the 13th is referred to as friggatriskaidekaphobia or paraskevidekatriaphobia. Friggatriskaidekaphobia is from Frigg, the Norse goddess of wisdom after whom Friday is named. The Greek words triskaideka, meaning 13, and phobia, meaning fear. Paraskevidekatriaphobia is also of Greek origin: paraskevi translates as Friday, and dekatria is another way of saying 13.

Friggatriskaidekaphobia affects millions of people. Also businesses, especially airlines suffer from severe losses on Friday the 13th. Because of fear of the number 13, many high-rise buildings, hotels, and hospitals skip the 13th floor. Many airports don’t have gates numbered 13. Many buildings don’t have a 13th floor, going right from 12 to 14, Also, many cities don’t have a 13th Street or 13th Avenue.

Friday the 13th Can Come in Threes
All years will have at least one Friday the 13th, but there cannot be more than three Friday the 13ths in any given calendar year. The longest one can go without seeing a Friday the 13th is 14 months.

Blame it on Sunday
For a month to have a Friday the 13th, the month must begin on a Sunday.

WHY IS FRIDAY THE 13TH BAD LUCK?

If your fear of Friday the 13th causes you to avoid traveling, going to work or eating in a restaurant on Friday the 13th, you have paraskevidekatriaphobia. Here are some superstitions about Friday the 13th and bad luck:

Don’t start a trip or new job

Don’t walk under a ladder

Don’t open an umbrella indoors

Never change your bed on a Friday as it will give you bad dreams.

Don’t sneeze over your left side

If you have 13 letters in your name, you will have the devil’s luck. For example, count the letters in these infamous names: Jack the Ripper, Charles Manson, Jeffrey Dahmer, Theodore Bundy and Albert De Salvo.