locust tree

CIDE DICTIONARY

locust tree, n. [Etymol. uncertain.].

 A large North American tree of the genus Robinia (Robinia Pseudacacia), producing large slender racemes of white, fragrant, papilionaceous flowers, and often cultivated as an ornamental tree. In England it is called acacia.  [1913 Webster]
" The name is also applied to other trees of different genera, especially to those of the genus Hymenæa, of which Hymenæa Courbaril is a lofty, spreading tree of South America; also to the carob tree (Ceratonia siliqua), a tree growing in the Mediterranean region."  [1913 Webster]

Honey locust tree (Bot.), a tree of the genus Gleditschia ) Gleditschia triacanthus), having pinnate leaves and strong branching thorns; -- so called from a sweet pulp found between the seeds in the pods. Called also simply honey locust. -- Water locust tree (Bot.), a small swamp tree (Gleditschia monosperma), of the Southern United States.