arsine

/AA0 R S IY1 N IY0/
noun
  1. 1

    A compound of arsenic and hydrogen, AsH3, a colorless and exceedingly poisonous gas, having an odor like garlic.

  2. 2

    Any organic derivative of this compound, or of diarsane, triarsane etc.

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