Webster's Revised Unabridged Dictionary · 1913

Iridaceous

Iridaceous , adjective

[From New Latin Iris, Iridis, the Iris.]

(Botany) Pertaining to, or resembling, a large natural order of endogenous plants (Iridacea), which includes the genera Iris, Ixia, Crocus, Gladiolus, and many others.

Also: Irideous