ly·can·thro·py [līˈkanTHrəpē] n. in folklore, the magical ability to assume the form and characteristics of a wolf.
Etymology: 1580s, a form of madness (described by ancient writers) in which the afflicted thought he was a wolf, from Greek lykanthropia, from lykanthropos "wolf-man," from lykos "wolf" (see wolf (n.)) + anthropos "man" (see anthropo-). Originally a form of madness (described by ancient writers) in which the afflicted thought he was a wolf; applied to actual transformations of persons (especially witches) into wolves since 1830 (see werewolf).
I'm sure we're all pretty familiar with this fun word, but it's always cool to see the etymology.
Note: today is my day to post at the main A to Z blog, so please come check out my post for L!