Webster’s Revised Unabridged Dictionary · 1913
Amianthus
Am′i·an′thus (·thŭs), n. [L. amiantus, Gr. ἀμίαντος λίθος (lit., unsoiled stone) a greenish stone, like asbestus; ἀ priv. + μιαίνειν to stain, to defile; so called from its incombustibility.] (Min.) Earth flax, or mountain flax; a soft silky variety of asbestus.