Yes, in the "Demon Slayer: Kimetsu no Yaiba" film "Mugen Train," Tanjiro Kamado loses his sword during the battle with the demon Enmu. During their fight, Enmu uses his ability to manipulate dreams and creates a scenario where Tanjiro's sword is swallowed by the Infinite Train.

As a result, Tanjiro is temporarily left without his sword, and he must rely on other means and techniques to continue the fight. However, Tanjiro later retrieves his sword with the help of his companions and regains the ability to wield it in subsequent battles.