Iridaceous \Ir`i*da"ceous\, Irideous \I*rid"e*ous\, a. [From NL. Iris, Iridis, the Iris.] (Bot.) Pertaining to, or resembling, a large natural order of endogenous plants ({Iridace[ae]}), which includes the genera {Iris}, {Ixia}, {Crocus}, {Gladiolus}, and many others.