abscission zone

noun

: the zone in a leaf petiole, fruit stalk, or branch often marked by a constriction within which is developed the separation layer, the vascular bundles in the zone usually being reduced in diameter, the sclerenchyma being weak or absent, the collenchyma lacking, and the cytoplasm of some of the parenchyma cells being denser than in adjacent cells

Word History

First Known Use

1904, in the meaning defined above

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