perspicacity

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
   • The citizens chose a university. They reasoned, with considerable perspicacity, that taxes come and go in response to political considerations, but a university, once established, is a permanent benefit to a city and a nation.1994, John H. Makin, Norman J. Ornstein, Debt and Taxes: How America Got into Its Budget Mess and What We Can Do about It, New York, NY: Times Books, →ISBN, page 52
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
   • As the former consists in the transmission of psychic states inappreciable to the normal perspicacity or senses, the transfer cannot pass through the medium of intelligence.1888, “Review of La suggestion mentale by H. Bourru and P. Burot”, in The American Journal of Psychology, volume 1, number 3, page 503
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