Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† asbestŏs, i, m. (sc. lapis), = ἄσβεστος (incombustible), a stone of an iron-gray color, found in Arcadia, differing from the common asbestos, perh. amiantus, Plin. 37, 10, 54, § 146.