Many believe that if all of the candles on a birthday cake are blown out with one breath, while making a silent wish, the wish will come true.
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There are numerous sailors' superstitions, such as: it is considered bad luck for a ship to set sail on a Friday, to bring anything blue aboard, to stick a knife into the deck, to leave a hatch cover upside-down, to say "pig", or to eat walnuts aboard.
70
Placing keys on a table is considered unlucky. (Sweden)
3
The superstitious symbolism of a black cat crossing one's path is dependent upon culture: some cultures consider this a sign of impending bad luck, while some cultures consider this a sign of impending good luck.
75
An acorn should be carried to bring luck and ensure a long life.
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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
9
When you speak of bad luck, it is said that one should always knock on wood. Also knocking when speaking of good luck apparently helps with having good luck. This is an old Celtic tradition related to belief of wood spirits.
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If you catch a falling leaf on the first day of autumn you will not catch a cold all winter.
394