acuity

Noun

• a quick and penetrating intelligence
  • he argued with great acuteness
    
  • I admired the keenness of his mind
    

• sharpness of vision; the visual ability to resolve fine detail (usually measured by a Snellen chart)

Related words

• Synonyms: 
  acuteness , sharpness , keenness , visual acuity , sharp-sightedness