Source : Webster's Revised Unabridged Dictionary (1913)

Arsine \Ar"sine\ ([aum]r"s[i^]n or -s[=e]n), n. [From
   {Arsenic}.] (Chem.)
   A compound of arsenic and hydrogen, {AsH3}, a colorless and
   exceedingly poisonous gas, having an odor like garlic;
   arseniureted hydrogen.

Source : WordNet®

arsine
     n : a poisonous colorless flammable gas used in organic
         synthesis and to dope transistors and as a poison gas in
         warfare