Hanging mistletoe over a doorway during the holiday season is a tradition around the world. But have you ever stopped to think about the story behind it? Where did it come from? Why do we kiss just because we're standing underneath some shrubbery?

Stockbyte/Getty Images The word "Mistletoe" is derived from the Old English words, "mistel" (dung) and "tan" (twig). The plant is thought to be named after bird droppings on a branch. See Christmas tree images.

In this article, you'll find out about mistletoe, how it grows and how it is spread. You'll learn about ancient people's understanding of biology and how they put it to use in their stories and myths. The next time you stand under mistletoe, you'll have a whole new understanding of this intriguing plant.

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The word "mistletoe" is derived from the Anglo-Saxon words, "mistel" (dung) and "tan" (twig) -- misteltan is the Old English version of mistletoe. It's thought that the plant is named after bird droppings on a branch [source: mwrop.org].

One of the beliefs in the early centuries was that mistletoe grew from birds. People used to believe that, rather than just passing through birds in the form of seeds, the mistletoe plant was an inherent result of birds landing in the branches of trees.

So how did this plant become entwined with Christmas? The holiday has assimilated a wide range of customs and traditions from many cultures, and mistletoe is one of them. For example, one French tradition holds that the reason mistletoe is poisonous is because it was growing on a tree that was used to make the cross on which Jesus Christ was crucified. Because of this, it was cursed and denied a place to live and grow on Earth, forever to be a parasite [source: Saupe].

In the next section, we'll look at the characteristics of mistletoe and learn how mistletoe seeds are spread.

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