When the holiday season comes around, most revelers place mistletoe under a doorway. While most people know it’s tradition to kiss under the mistletoe, not many people know why. To find out more about the custom, continue reading below for some fun facts, courtesy of Today I Found Out, Why Christmas and The Holiday Spot:

Mistletoe is a parasite that attaches itself to other trees. While mistletoe promotes wildlife as a source of food, it’s poisonous for humans to eat. It has leathery leaves and grows on apple, oak, and other broadleaf trees. It produces white gooey berries in winter.

Entomology of the name: Mistletoe has a name meaning that would make school kids— or the young at heart—giggle into their hands. Mistletoe gets its moniker because the plant blossoms after bird drippings fall on trees.

The plant was given the name “misteltan,” which comes from the Old English word “mistel,” which is the word for poop. “Tan” is the plural of “ta,” which means, twig. Put it all together and mistletoe essentially means poop on a stick. Not exactly the most romantic word, is it?

Why people kiss under mistletoe, aka poop twig: The tradition dates back to the Celts, the Babylonians and Ancient Greeks.

For the Ancient Greeks, mistletoe helped fertility, was an aphrodisiac and could be used to achieve eternal life.

The Celts considered mistletoe to be a plant of peace. If they crossed under the mistletoe with an enemy, they would stop fighting for at least a day. Mistletoe then morphed into a symbol for good luck.

The mistletoe tradition known today is closest related to the way the Babylonions used it. A woman who wanted to find a mate would stand outside the temple that belonged to the goddess of love. Of course, mistletoe hanged in the entry. When a suitor arrived, the woman was supposed to bond with him.

How mistletoe evolved to the way it is known today: People in 18th century Britain would compile mistletoe into a ball and then hang it in the doorway. A couple would kiss under the mistletoe ball if it still had berries. Each time they kissed, a berry, which contained good luck, would be removed from the plant. If there weren’t any more berries left, the mistletoe would then be considered bad luck.

Another English legend claims that a girl who stands under mistletoe cannot refuse a kiss. A deep kiss could bring long lasting friendship or romance.

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