1. strong stiff wood of a black-locust tree; very resistant to decay • Hypernyms: wood • Substance Holonyms: yellow locust, Robinia pseudoacacia 2. large thorny tree of eastern and central United States having pinnately compound leaves and drooping racemes of white flowers; widely naturalized in many varieties in temperate regions • Syn: yellow locust, Robinia pseudoacacia • Hypernyms: locust tree, locust • Member Holonyms: Robinia, genus Robinia