What does "blight" mean?

Blight: Hence: To destroy the happiness of; to ruin; to mar essentially; to frustrate; as, to blight one's prospects. Seared in heart and lone and blighted. Byron.

Additional senses

  1. 2.To be affected by blight; to blast; as, this vine never blights.
  2. 3.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.
  3. 4.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.
  4. 5.That which frustrates one's plans or withers one's hopes; that which impairs or destroys. A blight seemed to have fallen over our fortunes. Disraeli.
  5. 6.(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.
  6. 7.pl. A rashlike eruption on the human skin. [U. S.]

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