li·chen·ous \ˈlīkənəs\adjective alsoli·chen·ose\-ˌnōs\ Etymology:lichen (I) + -ous or -ose 1. a.: of, relating to, or resembling lichens b.: abounding in or covered with lichens < a stone seat stood at one end, a fountain at the other, both lichenous and crumbling — Frederic Prokosch > 2.: of or relating to lichen : lichenoid