Lilium is the plant genus of "true lilies".

Lilium may also refer to:

• the Latin term for the fleur-de-lis emblem
• Lilium (constellation), a constellation defined by Augustin Royer in 1679
• 1092 Lilium, a minor planet, discovered in 1924
• Lilium (band), a French-American band
• "Lilium," the opening theme song from the anime Elfen Lied
• Lilium GmbH, a German start-up developing an electric airplane
  • Lilium Jet, an electric airplane developed by Lilium
• Lilium Tower, a proposed skyscraper project for Warsaw, Poland

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