The Collaborative International Dictionary of English v.0.48:
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.
[1913 Webster]