Abscission or Frustration

When a planet is simultaneous forming an aspect to two other planets, the one that culminates first may produce an abscission of light that will frustrate the influence of the second aspect. The term was much used by ancient writers, but unfortunately has been neglected by modern astrologers — other than those who practice Horary astrology

DeVore, Nicholas. Encyclopedia of Astrology. New York: Philosophical Library, 1947.