English▸ noun [mass noun] Botany the natural detachment of parts of a plant, typically dead leaves and ripe fruit:
leaf abscission in trees
[as modifier] abscission layer.
– ORIGIN mid 16th century (in the sense ‘action or process of cutting off’): from late Latin abscissio(n-), from Latin abscindere, from ab- ‘off’ + scindere ‘to cut’. The botanical sense dates from the late 19th century.