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Noun: hydrogen  hI-dru-jun
  1. A nonmetallic univalent element that is normally a colourless and odourless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe
    - H, atomic number 1

Derived forms: hydrogens

Type of: chemical element, element, gas

Part of: H2O, water

Encyclopedia: Hydrogen