: a subclass of Angiospermae comprising seed plants (such as cactuses and oaks) that produce an embryo with two cotyledons and have net-veined leaves, stems with secondary thickening resulting in annual ring formation in woody perennials, and floral organs usually arranged in cycles of four or five, including most of the deciduous woody plants of temperate climates and the majority of herbaceous flowering plants, and commonly being divided into Archichlamydeae and Metachlamydeae compare monocotyledoneae
Word History
Etymology
New Latin, alteration of Dicotyledones, from di- + cotyledones, plural of cotyledon
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