argon

/ˈɑːɹɡɒn/

IPA: /AA1 R G AA0 N/

noun
  1. 1

    The chemical element (symbol Ar) with an atomic number of 18. The third most abundant gas in the Earth's atmosphere, it is a colourless, odourless, inert noble gas.

  2. 2

    A single atom of this element.

Source: https://en.wiktionary.org/wiki/argon