old-man's-beard \ˈ ̷ ̷ˌ ̷ ̷ˈ ̷ ̷\noun 1.: any of several clematises: as a.: an American virgin's bower (Clematis virginiana) b.: a European traveler's-joy (C. vitalba) 2. a.: spanish moss b.: beard lichen 3.: fringe tree 4.dialect England: any of several plants of the genus Equisetum