In Assassin's Creed, what is the name of Altaïr Ibn-La'Ahad's main weapon?

In Assassin's Creed, Altaïr Ibn-La'Ahad's main signature weapon is the Hidden Blade.

The Hidden Blade is a concealed wrist-mounted weapon used by members of the Assassin Brotherhood. It is designed for discreet attacks and is normally extended from beneath the user's sleeve. Altaïr carries the weapon during his missions in the Holy Land, where stealth and concealment are central to the Brotherhood's methods.

In the first game, Altaïr's equipment is closely associated with Assassin traditions, including climbing, blending into crowds, and striking targets from close range. The weapon later becomes one of the most recognizable symbols of the entire franchise, even though different protagonists use different versions and upgrades.

Players sometimes confuse the Hidden Blade with the series' other weapons, such as swords, daggers, or throwing knives. Those weapons are useful in open combat, whereas the Hidden Blade is chiefly identified with covert assassination. Later entries add paired blades, retractable variants, and specialized mechanisms.