Krypton

noun
  1. A chemical element with the symbol Kr and atomic number 36. It is a colorless, odorless, tasteless noble gas that occurs in trace amounts in the Earth's atmosphere. Krypton is used in lighting and photography. noun
    Krypton is often used in fluorescent lamps and flash photography.
    The noble gas krypton is known for its lack of chemical reactivity.
  2. In popular culture, particularly in comic books, krypton is the fictional home planet of the superhero Superman. noun
    Superman was born on the planet Krypton before being sent to Earth.
    The destruction of Krypton is a pivotal event in Superman's origin story.