\Phos"phine\, n. (Chem.)
A colorless gas, {PH3}, analogous to ammonia, and having a
disagreeable odor resembling that of garlic. Called also
{hydrogen phosphide}, and formerly, {phosphureted hydrogen}.
Note: It is the most important compound of phosphorus and
      hydrogen, and is produced by the action of caustic
      potash on phosphorus. It is spontaneously inflammable,
      owing to impurities, and in burning produces peculiar
      vortical rings of smoke.