Friday the 13th sounds unlucky ? Traditional superstition ? And a lot of people dislike it and believe it to be unfortunate. A Friday occurring on the 13th day of any month is considered to be a day of bad luck in English and Portuguese-speaking cultures around the world. And similar superstitions exist in some other traditions. The fear of Friday the 13th is called paraskavedekatriaphobia or paraskevidekatriaphobia (horribly long words). Read more... ...