cactus

n. (pl. -ti or cactuses) plant with a thick fleshy stem and usu. Spines but no leaves. [latin from greek]

n. Any plant of the order Cactacae, as the prickly pear and the night-blooming cereus. See Cereus. They usually have leafless stems and branches, often beset with clustered thorns, and are mostly natives of the warmer parts of America.