Abscission occurs when, one of the significators first aspects a slower planet, or a faster planet first aspects one of the significators, before an aspect between two significators can perfect. In either case, the light of the approaching significator is cut off by the rays of the third planet, which fall, by aspect or conjunction, between the two others which are forming an aspect. Symbolically, abscission may interfere with whatever is promised by the forming aspect between significators. The "cutting off" or preventing of anything shown by one aspect, by means of another.
Comments: Abscission of Light