pteridoid,a.andn.|pt-, ˈtɛrɪdɔɪd| [f.Gr. πτερίς, πτεριδ- fern + -oid.] a.adj. Of the nature of or allied to the ferns, filicoid. b.n. A fernlike plant; a pteridophyte. 1866Pall Mall G. 12 Sept. 10 His treatise on the culture of pteridoids... Cultivation of the pteridoid forms of life.