page_title: Glossary of botanical terms
section_title: N
hierarchical_section_title: Glossary of botanical terms / N
caption_attribution_description: English: A flower of Helleborus argutifolius showing the 5 petal-like sepals, the whorl of small petals transformed into nectaries, the stamens and the styles.
context_page_description: This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary of leaf morphology.
context_section_description: native
  Naturally occurring in an area, but not necessarily confined to it. Compare endemic.
  natural hybrid
  A hybrid taxon produced by chance in the wild.
  naturalised
  Describing a plant, introduced from another region, that grows and reproduces readily in competition with the natural flora.
  nectar
  A usually sweet, nutrient-rich fluid produced by the flowers of many plants and collected by bees and other insects.
  nectary
  A specialized gland that secretes nectar.
  neophyte
  A plant that has recently been introduced to a geographic area. Contrast archaeophyte.
  nerve
  Another name for a vein.
  node
  The part of a stem from which leaves or branches arise.
  nomen conservandum
  (Latin) A conserved name, usually a name that became so much better known than the correct name, that a substitution was made.
  nomen illegitimum
  A name that is either superfluous at its time of publication because the taxon to which it was applied already has a name, or the name has already been applied to another plant (a homonym).
  nomen invalidum
  A name that is not validly published, and technically is therefore not a botanical name. Abbreviation: nom. inval. See valid publication.
  nomen nudum
  A name not published in accordance with the International Code of Nomenclature for algae, fungi, and plants, usually without a diagnosis or description of the entity to which it applies, and without reference to either; such a name should not be used.
  nomenclature
  The naming of things; often restricted to the correct use of scientific names in taxonomy; a system that sets out provisions for the formation and use of names.
  noxious
  Of plants, containing harmful or unwholesome qualities. Applied in conjunction with 'weed' to specifically describe a plant which legislation deems harmful to the environment. Each state and territory in Australia has specific legislation governing noxious weeds.
  nucellus
  The tissue of the ovule of a seed plant that surrounds the female gametophyte. It is enclosed by integuments and is not of epidermal origin.
  numerous
  Stamens are described as numerous when there are more than twice as many as sepals or petals, especially when there is no set number of them. Compare indefinite
  nut
  A hard, dry, indehiscent fruit containing only one seed.
  nutlet
  1.  A small nut.
  2.  One of the lobes or sections of the mature ovary of some members of the Boraginaceae, Verbenaceae, and Lamiaceae.
caption: Helleborus argutifolius has its small green petals modified into floral nectaries. The sepals function as petals
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