Blight

n.
  1. Mildew; decay; anything nipping or blasting; -- applied as a general name to various injuries or diseases of plants, causing the whole or a part to wither, whether occasioned by insects, fungi, or atmospheric influences.
  2. The act of blighting, or the state of being blighted; a withering or mildewing, or a stoppage of growth in the whole or a part of a plant, etc.
  3. That which frustrates one's plans or withers one's hopes; that which impairs or destroys.
  4. (Zoöl.) A downy species of aphis, or plant louse, destructive to fruit trees, infesting both the roots and branches; -- also applied to several other injurious insects.