noun (n)

• a quick and penetrating intelligence

  cepat dan menembus intelijen

  Example:
  I admired the keenness of his mind.
  

  Synonym:
  acuity, acuteness, sharpness
  

  source: wordnet30
• a positive feeling of wanting to push ahead with something

  yang positif perasaan ingin mendorong di depan dengan sesuatu

  Synonym:
  avidity, avidness, eagerness
  

  source: wordnet30
• thinness of edge or fineness of point

  nipis dari pinggir atau fineness dari titik

  Synonym:
  sharpness
  Antonym:
  bluntness, dullness
  

  source: wordnet30
• The quality or state of being keen.

  kualiti atau keadaan menjadi tajam.

  source: webster1913