abscission ab·scis·sion (āb-sĭzh'ən)
The act of cutting off or away.
The separation of a leaf, flower, or fruit from a plant as a result of natural structural and chemical changes. ◇ The abscission zone is a layer of weak, thin-walled cells that form across the base of the plant part where the break eventually occurs. A corky layer containing suberin forms beneath the abscission zone to protect the plant.