Orris Absolute is from the plant Iris pallida, the Dalmatian iris or sweet iris, is a hardy flowering perennial plant of the genus Iris, family Iridaceae. It is native to the Dalmatian coast (Croatia) but widely naturalised elsewhere. It is a member of the subgenus Iris, meaning that it is a bearded iris, and grows from a rhizome.
Orris Absolute (aromatherapy)
The absolute is a water-white or very pale yellow, oily liquid of extremely delicate, sweet-floral, yet somewhat woody odor which appears very weak at first, but later, or on dilution, displays its full and impressive strength and diffusion.
Arctander, Steffen . Perfume and Flavor Materials of Natural Origin (p. 574).