Lightsaber

Short for lightsaber.

From the official Star Wars website databank:
The lightsaber is the weapon of a Jedi, an elegant armament of a more civilized time. In comparison, blasters are crude, inaccurate and loud affairs. To carry a lightsaber is an example of incredible skill and confidence, dexterity and attunement to the Force.

When deactivated, a lightsaber appears as a polished metallic handle, about 30 centimeters long, lined with control studs. At the press of a button the energy contained within is liberated and forms as a shaft of pure energy about a meter long. The saber hums and scintillates with a distinct sound. Its shimmering blade is capable of cutting through almost anything, save for the blade of another lightsaber.

In the hands of a Jedi, a lightsaber is almost unstoppable. It can be used to cut through blast doors or enemies alike. Using the Force, a Jedi can predict and deflect incoming blaster bolts, and reflect them back at the firer.

Lightsabers were often passed down by masters to padawans or through a Jedi family. During the Jedi Purge where Darth Vader was ordered by Emperor Palpatine to exterminate the remaining Jedi, a couple of resourceful Jedi left their lightsabers for their children for a time when the Jedi Order would be revived.

In addition to the above information, lightsabers come in two common forms as seen in the game, Jedi Academy. These two forms are single blade and dual blade, also known as staff. The dual phase lightsaber is a rare type, possessing two blade length settings, usually changed by twisted the lightsaber handle. Popular examples of single blade lightsaber users are Darth Vader, Obi-Wan Kenobi, Mace Windu, Luke Skywalker, Yoda, and most of the Jedi and Sith. Darth Maul is a well-known staff user. From the Expanded Universe, Corran Horn is the most famous dual phase user.