Poison bush \Poison bush\ In Australia: (a) Any fabaceous shrub of the genus {Gastrolobium}, the herbage of which is poisonous to stock; also, any species of several related genera, as {Oxylobium}, {Gompholobium}, etc. (b) The plant {Myoporum deserti}, often distinguished as {Ellangowan poison bush} or {dogwood poison bush}. (c) The ulmaceous plant {Trema cannabina}, which, though not poisonous, is injurious to stock because of its large amount of fiber. [Webster 1913 Suppl.]