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Noun: Au
  1. A soft yellow malleable ductile (trivalent and univalent) metallic element; occurs mainly as nuggets in rocks and alluvial deposits; does not react with most chemicals but is attacked by chlorine and aqua regia
    - gold, atomic number 79
Noun: AU
  1. A unit of length used for distances within the solar system; equal to the mean distance between the Earth and the Sun (approximately 93 million miles or 150 million kilometres)
    - Astronomical Unit

Derived forms: AUs, Aus

Type of: astronomy unit, noble metal

Part of: dental gold, gold, gold foil, gold leaf, graphic tellurium, sylvanite

Encyclopedia: Au, Vorarlberg

AU