Lycanthrope

A Lycanthrope; also known as Werewolf; can be defined as a humanoid who periodically experiences an involuntary form of shape-shifting and is transformed into a lupine creature.

The transformation is usually triggered by the light of a full moon, although this isn't necessarily always so. The condition may be transmitted to others that are bitten by the Werewolf. How much the Werewolf retains or fails to retain his or her sapience and self-control may vary, but they most commonly become feral. They are generally weak to silver, and sometimes can only be killed by a silver bullet.

Strictly speaking, the term "Lycanthrope" applies to both genders, whereas "Werewolf" is a male term; the female equivalent being "Wifwolf", which isn't commonly used.

In popular culture

 * Lycanthropes from Roswell Conspicaries
 * Martian Werewolf from Face Off
 * Neptunian Werewolf from Face Off
 * Saturnian Werewolf from Face Off
 * Vulpanans from Doctor Who