Irrlicht may refer to:

• Irrlicht, the German name for will-o'-the-wisp, the ghostly light sometimes seen at night over bogs and swamps
• "Irrlicht", the ninth song in the Winterreise cycle by Franz Schubert
• Irrlicht (album), by Klaus Schulze
• Irrlicht Engine, a 3D computer graphics engine
• Die Irrlichter, a German mediaval/fantasy/folk band
• Irrlicht (film), a 1919 German silent film

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