What is "water locust tree"

Locust tree \Lo"cust tree`\n. [Etymol. uncertain.] (Bot.) 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.

Note: The name is also applied to other trees of different genera, especially to those of the genus Hymen[ae]a, of which Hymen[ae]a Courbaril is a lofty, spreading tree of South America; also to the carob tree ( Ceratonia siliqua), a tree growing in the Mediterranean region.

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.