a. [ Pref. in- not + combustible: cf. F. incombustible. ] Not combustible; not capable of being burned, decomposed, or consumed by fire; uninflammable; as, asbestus is an incombustible substance; carbon dioxide is an incombustible gas. [ 1913 Webster ]

Incombustible cloth, a tissue of amianthus or asbestus; also, a fabric imbued with an incombustible substance.

-- In`com*bus"ti*ble*ness, n. -- In`com*bus"ti*bly, adv. [ 1913 Webster ]