Noun | 1. | ![]() genus Yucca - tropical American plants with stiff lancelike leaves and spikes of white blossoms; sometimes considered a genus of Amaryllidaceae Yucca aloifolia, Spanish bayonet - a stiff yucca with a short trunk; found in the southern United States and tropical America; has rigid spine-tipped leaves and clusters of white flowers Spanish bayonet, Yucca baccata - tall yucca of the southwestern United States and Mexico having a woody stem and stiff swordlike pointed leaves and a large cluster of white flowers Joshua tree, Yucca brevifolia - a large branched arborescent yucca of southwestern United States having short leaves and clustered greenish white flowers Yucca carnerosana, Spanish dagger - arborescent yucca of southwestern United States and northern Mexico with sword-shaped leaves and white flowers Adam's needle, Adam's needle-and-thread, needle palm, spoonleaf yucca, Yucca filamentosa - yucca with long stiff leaves having filamentlike appendages Yucca glauca, bear grass - yucca of west central United States having a clump of basal grasslike leaves and a central stalk with a terminal raceme of small whitish flowers Spanish dagger, Yucca gloriosa - yucca of southeastern United States similar to the Spanish bayonets but with shorter trunk and smoother leaves bear grass, Yucca smalliana - yucca of southern United States having a clump of basal grasslike leaves and a central stalk with a terminal raceme of small whitish flowers Our Lord's candle, Yucca whipplei - yucca of southwestern United States and Mexico with a tall spike of creamy white flowers |