Laurel refers to any of various similar trees or shrubs of the laurel family, Lauraceae.
Most of them have an aromatic bark and foliage, which are evergreen, and some are even used to make aromatic oils and spices.
The true laurel, Laurus nobilis, is the one mentioned in history; used to make triumphal crowns for victors. It is a Mediterranean evergreen tree, also called bay, sweet bay or bay laurel. It has deep green leaves, which are used in cookery, and purple berries.
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"Laurel." Infoplease. Person Education, n.d. Web. 09 Dec. 2013. <http://www.infoplease.com/encyclopedia/science/laurel-botany.html>.