You often hear kids say, "sticks and stones may break my bones, but words will never hurt me." The entries on this list suggest otherwise. This list is full of forbidden words and phrases throughout history that can allegedly cause harm if they're spoken out loud (or, in some cases, even if they're written down).
These supposedly dangerous words and names come from different religions, mythologies, rituals, and superstitions from all across the globe. Some, like the fear of "summoning" bears, actually had a long-term impact on the English language. Others, like the theatrical prohibitions against saying "Macbeth" or "Good luck," are just pure superstition. The religious word and name taboos, while odd to non-believers, are taken very seriously by practitioners.
As such, you might want to read this list of forbidden words silently and not aloud...
Ever wonder why the English word for “bear” sounds nothing like the Latin word ursus or the Greek word arktos? According to Ralph Keyes’s Euphemania: Our Love Affair with Euphemisms, the oldest known euphemism was the Proto-Germanic beorn (literally "the brown one") which early Northern Europeans used a thousand years ago or so instead of the “real” name for a bear.
Why? Because uttering their equivalent of "bear" might summon them. The Online Etymology Dictionary claims the “blood-thirsty beast that shall not be named,” therefore fear was pretty common. The Irish name for a bear was "the good calf," the Welsh called it the "honey-pig," the Lithuanians called it "the licker," and the Russians said medved, or "honey-eater.”
This one is about being terrified of writing a word, but the idea is the same. The fear of syphilis was so strong in the 15th and 16th centuries, according to Paul Chrystal’s In Bed with the Ancient Greeks, that doctors would use the Greek letter sigma as a symbol for syphilis for fear that writing the word might somehow evoke it.
Syphilis - or, uh, “Σ” - is named after a mythological shepherd named Syphilus "who was cursed by the god Apollo with a dread disease."
Even modern medical textbooks (such as David Allison and Dr. Nicola Strickland’s Acronyms and Synonyms in Medical Imaging) still advise students of the possible use of “Σ” in place of the word syphilis.
Unless you are rehearsing or performing Macbeth, saying "Macbeth" in a theater will bring bad luck at the least and outright disaster at the worst. Actors believe the play is cursed because of its history; two different actors have actually died on stage while performing it. The play also was at the center of a deadly riot. Some believe Shakespeare was cursed by witches offended by the play - or even that the playwright intentionally cursed the play himself by putting real spells into the witches' dialogue.
If you must allude to Macbeth in a theater, it's better to call it "the Scottish play" instead.
Urban legend has it that if you look into a mirror in a room lit only by a candle and chant "Bloody Mary" repeatedly, an apparition will appear in the mirror. What exactly you will see varies from teller to teller, but most agree that a woman will appear and do something absolutely terrifying. An older version of this myth said that if young, unmarried women looked into a mirror while holding a candle, they could catch a glimpse of their future husbands. In Japan, a similar legend is told about Hanako-san, a young girl who appears in the mirrors of school bathrooms when students call her name.
Scientists have suggested that staring into a mirror in a dimly lit room and chanting can cause one to hallucinate, or even to hypnotize themselves - a more probable, if less spooky, explanation for this effect.