• (n.) One of an extinct family of trees allied to the modern club mosses, and including Lepidodendron and its allies.
Lep`i·do·den'drid (lĕp`ĭ*do*dĕn'drĭd) noun (Paleon.) One of an extinct family of trees allied to the modern club mosses, and including Lepidodendron and its allies. 
lepidodendrid, lepidodentroid A reference to one of an extinct family of trees allied to the modern club mosses, and including Lepidodendron and its allies.