Orris

Orris root is the root of some species of iris, grown principally in southern Europe: Iris germanica, Iris florentina, and Iris pallida. Once important in western herbal medicine, it is now used mainly as a fixative and base note in perfumery, as well as an ingredient in many brands of gin (perhaps most famously in Bombay Sapphire gin). Orris root must generally be hung and aged for 5 years before it can be used for perfumery. This substance is left out of products that are labeled hypo-allergenic