| Noun | 1. | Pteridophyta - containing all the vascular plants that do not bear seeds: ferns, horsetails, club mosses, and whisk ferns; in some classifications considered a subdivision of Tracheophytadivision - (botany) taxonomic unit of plants corresponding to a phylum order Psilophytales, Psilophytales - Paleozoic simple dichotomously branched plants of Europe and eastern Canada including the oldest known vascular land plants | |