Joshua tree
n.
A tall branching yucca plant (Yucca brevifolia) of the southwest United States, having large clusters of greenish-white flowers.
[Probably after JOSHUA1, from the resemblance of the tree's greatly extended branches to Joshua's outstretched arm as he pointed with his spear to the city of Ai (Joshua 8:18).]
Joshua treeYucca brevifolia