from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Sharpness of vision, especially as tested with a Snellen chart. Normal visual acuity based on the Snellen chart is 20/20.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. sharpness of vision; the visual ability to resolve fine detail (usually measured by a Snellen chart)
Sorry, no etymologies found.