Dictionary.net

cone-bearing gymnosperms dating from the Carboniferous period; most are substantial trees; includes the classes Pinopsida (subdivision Pinophytina) and Ginkgopsida (subdivision Ginkgophytina) and Taxopsida (subdivision Taxophytina) which in turn include the surviving orders Coniferales and Taxales (yews) and sometimes Ginkgoales as well as extinct orders such as Cordaitales (of the Carboniferous and Permian)

Gymnosperms are a group of vascular plants whose seeds are not enclosed by a ripened ovary (fruit). Gymnosperms are distinguished from the other major group of seed plants, the angiosperms, whose seeds are surrounded by an ovary wall. The seeds of many gymnosperms (literally, "naked seed") are borne in cones and are not visible. Taxonomists now recognize four distinct divisions of extant gymnospermous plants (Coniferophyta, Cycadophyta, Ginkgophyta, and Gnetophyta).