class Dicotyledones

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Definition

Noun: A major taxonomic class of flowering plants (angiosperms) characterized by seeds that contain an embryo with two initial leaves (cotyledons) and typically having leaves with a branching, net-like vein pattern. This class historically encompassed a broad grouping now more commonly referred to as "dicots" or "eudicots," and it included several subclasses.

Usage

The term "class Dicotyledones" is used in botanical classification and scientific contexts to refer to this large group of plants. * Botanists once placed most flowering plants into either the class Dicotyledones or the class Monocotyledones. * The classification "class Dicotyledones" includes families like the rose family and the sunflower family.

Advanced Usage
  • Taxonomic Context: In modern phylogenetic systems (like the APG system), the traditional "dicots" are recognized as not being a single, natural group. The term "class Dicotyledones" is therefore considered somewhat outdated in strict scientific taxonomy, though it remains useful for historical and educational purposes to describe a set of shared morphological characteristics.
    • The concept of class Dicotyledones is paraphyletic, meaning it does not include all the descendants of a common ancestor.
Variants and Related Words
  • Dicotyledonae: An alternative name for the same class.
  • Dicotyledones: The singular form is rarely used; the class name is typically treated as a plural noun.
  • Dicot (noun/informal): A common abbreviation for a plant belonging to this class.
    • Beans and oaks are typical dicots.
  • Eudicot (noun): A modern term for the largest monophyletic group within the former dicots, representing the "true dicots."
    • Most plants formerly called dicots are now classified as eudicots.
Synonyms
  • Dicots
  • Magnoliopsida (in some classification systems, this is the formal name for the class)
Related Terms (Not Synonyms)
  • Monocotyledones / Monocots: The other major traditional class of angiosperms, characterized by a single cotyledon.
  • Cotyledon: The embryonic leaf within the seed, the number of which (one or two) defines the traditional class names.
  • Angiosperm: The broader group (flowering plants) to which both dicots and monocots belong.
Noun
  1. comprising seed plants that produce an embryo with paired cotyledons and net-veined leaves; divided into six (not always well distinguished) subclasses (or superorders): Magnoliidae and Hamamelidae (considered primitive); Caryophyllidae (an early and distinctive offshoot); and three more or less advanced groups: Dilleniidae; Rosidae; Asteridae

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