Acorus: A plant genus of the family ACORACEAE, order Arales, subclass Arecidae most notable for Acorus calamus L. root which contains asarone and has been used in TRADITIONAL MEDICINE.Rhizome: Root-like underground horizontal stem of plants that produces shoots above and roots below. Distinguished from true roots which don't have buds and nodes. Similar to true roots in being underground and thickened by storage deposits.Polygala: A plant genus of the family POLYGALACEAE that contains onjisaponins, xanthones, pyrones, and benzophenones. The name is similar to other snakeroots such as ASARUM; SANICULA; ARISTOLOCHIA; AGERATINA; and others.Anisoles: A group of compounds that are derivatives of methoxybenzene and contain the general formula R-C7H7O.Iridaceae: A monocot plant family of the Liliopsida class. It is classified by some in the Liliales order and some in the Asparagales order.Oils, Volatile: Oils which evaporate readily. The volatile oils occur in aromatic plants, to which they give odor and other characteristics. Most volatile oils consist of a mixture of two or more TERPENES or of a mixture of an eleoptene (the more volatile constituent of a volatile oil) with a stearopten (the more solid constituent). The synonym essential oils refers to the essence of a plant, as its perfume or scent, and not to its indispensability.