from The American Heritage® Dictionary of the English Language, 4th Edition
- transitive v. To cut off; remove.
- intransitive v. To shed by abscission.
from The Century Dictionary and Cyclopedia
- To cut off or away.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- v. shed flowers and leaves and fruit following formation of a scar tissue
- v. remove or separate by abscission
And once the hormone level reaches to a certain point, that induces the organ shed, basically, the leaves or the fruits or flower petals or whatever it is that can abscise from their tree or plant.