or 20/20

[ twen-tee-twen-tee, twuhn-tee-twuhn-tee ]
See synonyms for twenty-twenty on
  1. Ophthalmology. having normal visual acuity.

  2. keenly or acutely perceptive: an opinion based on twenty-twenty hindsight.

Origin of twenty-twenty

First recorded in 1875–80; extracted from Ophthalmic Manual (1875), by Sir Thomas Longmore, chief medical officer of the British armed forces

Words Nearby twenty-twenty Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use twenty-twenty in a sentence

British Dictionary definitions for twenty-twenty


  1. med (of vision) being of normal acuity: usually written 20/20

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for twenty-twenty


  1. Having normal visual acuity. A person with twenty-twenty vision can see type as small as one-third of an inch at a distance of twenty feet.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.