Bad luck is an unpredictable outcome that is unfortunate. This is a list of signs believed to bring bad luck according to superstitions.

List

• Breaking a mirror is said to bring seven years of bad luck^[1]
• A bird or flock of birds going from left to right (Auspicia) (Paganism)^{[citation needed]}
• Certain numbers:
  • The number 4. Fear of the number 4 is known as tetraphobia; in Chinese, Japanese, and Korean languages, the number sounds like the word for "death".^[2][3][4][5]
  • The number 9. Fear of the number 9 is known as enneaphobia, in Japanese culture; this is because it sounds like the Japanese word for "suffering".^[4][5]
  • The number 13. Fear of the number 13 is known as triskaidekaphobia.
  • The number 17. Fear of the number 17 is known as heptadecaphobia and is prominent in Italian culture.^[6]
  • The number 39. Fear of the number 39 is known as the curse of 39, especially in Afghan culture.^[7]
  • The number 43. In Japanese culture, maternity wards numbered 43 are considered taboo, as the word for the number means "still birth".^{[dubious – discuss][8]}
  • The number 666. Fear of the number 666 is known as hexakosioihexekontahexaphobia. Per Biblical prophesy, the "Number of The Beast", signifies the return of the Devil and Antichrist. Also called the "Mark of the Beast", wherein all humans will have it on their forehead or hand.
• Friday the 13th (in Spain, Greece, and Georgia: Tuesday the 13th)^{[citation needed]}
• Failing to respond to a chain letter^[9]
• Giving a clock as a gift in Chinese culture, as in Chinese, to give a clock (Chinese: 送鐘/送钟; pinyin: sòng zhōng) has the same pronunciation as "sending off for one's end" (Chinese: 送終/送终; pinyin: sòngzhōng).^[10]
• Hanging a horseshoe with the ends pointing down, as it is believed that the luck will 'fall out'^[11]
• Opening an umbrella while indoors^{[12]: 204, 267}
• On the Isle of Man, rats are referred to as "longtails" as saying "rat" is considered bad luck.^[13][14]
• Navajo culture:
  • pointing at a rainbow^{[15][better source needed][16]}
  • throwing rocks into the wind^[15][16]
  • a coyote crossing one's path^[15] heading north^[16]
  • an owl^[17] flying over a house.^{[citation needed]}
• Placing chopsticks straight up in a bowl of rice in Chinese and Japanese culture is reminiscent of food offerings left for the dead.^[18]
• Ravens, crows and magpies^{[12]: 385–386, 243, 386}
• Saying the word "Macbeth" or wishing someone "Good Luck" while inside a theatre^[19]
  • The substitutions "The Scottish Play" and "Break a leg" are used instead.
• Shoes on a table
• Placing a hat on a bed ^[20]
• Three on a match^[12]: 292
• Tipping a salt shaker over^[12]: 188
• Viewing one's doppelgänger may be considered a harbinger of bad luck^{[citation needed]}
• Killing a ladybug^[21][22]
• Walking under a ladder^[23][24]
• Black cat crossing one's path^[12]: 294
• Picking up a penny with the tails side up ^[25][26]