English

Noun

visual acuity ‎(countable and uncountable, plural visual acuities)

1. The sharpness of vision or sight.
   • 1899, "Progress of medicine", The Memphis Lancet, page 216:

     The Italian railroads require of their employes both eyes normal in regard to visual acuity, ocular refraction, perception of red and green, and visual field.

2. Strength of vision expressed on some definite scale.
   • 1896, Annales d'Oculistique English edition, page 307:

     Myopia exceeding 6 D., provided the visual acuity exceed 1/4 for one of the eyes and 1/16 for the other, and there be no extended choroidal lesions.