cultivar

A cultivar is a cultivated plant that has been selected and given a unique name because it has desirable characteristics (decorative or useful) that distinguish it from otherwise similar plants of the same species. When propagated it retains those characteristics.The naming of a cultivar should conform to the International Code of Nomenclature for Cultivated Plants (the ICNCP, commonly known as the "Cultivated Plant Code"). For this, it must be distinct from other cultivars and it must be possible to propagate it reliably, in the manner prescribed for that particular cultivar.
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Noun
1. a variety of a plant developed from a natural species and maintained under cultivation
(hypernym) variety

v. cultivate, prepare the ground for planting, grow crops; develop

v. cultivate, husband; farm, plant; polish; reclaim; improve

n. cultivar, cultivated variety