Where did the word assassin come from?

While mounting a jihad against the invading Christian Crusaders in the 1300s, Hassan ben Sabah controlled his command of radical killers with a potion that gave them dreams of an eternity in a garden where young women pleased them to their heart’s content. The potion was from hashish, and these young killers became known as hashish eaters, which in Arabic is hashashin, or as the Crusaders pronounced it, “assassin.”