| Noun | 1. | costusroot - annual herb of the eastern Himalayas (Kashmir) having purple florets and a fragrant root that yields a volatile oil used in perfumery and for preserving furs genus Saussurea, Saussurea - genus of herbs of temperate and cool regions of Eurasia herb, herbaceous plant - a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests |