perspicacities

Noun

perspicacity (usually uncountable, plural perspicacities)

1. (usually) Acute discernment or understanding; insight.
   • "I understand," I said. "The fact is that you have the money." His face brightened. He seemed pleased at my perspicacity.1904, Jack London, chapter 8, in The Sea-Wolf (Macmillan’s Standard Library), New York, N.Y.: Grosset & Dunlap, →OCLC
2. (usually) The human faculty or power to mentally grasp or understand clearly.
   • His very veneration for his father-in-law, combined as it is with a total want of the most ordinary perspicacity, is an additional disqualification.1856, “Selections from the Letters of Robert Southey”, in The Quarterly Review, volume 98, page 458
3. (obsolete, usually) Keen eyesight.
   • Attentive consideration of the phenomena of vision has led to the invention of artificial aids by which the sight may be wonderfully strengthened and preserved, and man endowed at once with the perspicacity of the eagle or the minute scrutiny of the insect.1833, John Harrison Curtis, A Treatise on the Physiology and Diseases of the Eye, London: Longman, page 138