op·ti·cal | \ˈäp-ti-kəl \

Definition of optical 

1 : of or relating to the science of optics

2a : of or relating to vision : visual

b : visible sense 1 optical wavelength

c : of, relating to, or being objects that emit light in the visible range of frequencies an optical galaxy

d : using the properties of light to aid vision an optical instrument

3a : of, relating to, or utilizing light especially instead of other forms of energy optical microscopy

b : involving the use of light-sensitive devices to acquire information for a computer optical character recognition

4 : of or relating to optical art

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Other Words from optical

optically \ˈäp-ti-k(ə-)lē \ adverb

Synonyms & Antonyms for optical


ocular, optic, visual



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Examples of optical in a Sentence

The company manufactures microscopes, telescopes, and other optical instruments. an optical illusion that fools most people

Recent Examples on the Web

Radiator panels will rotate into place, its main high-gain antenna will deploy and the giant five-layer sunshield will open and stretch into position to shade the optical system. William Harwood, CBS News, "Launch of NASA's James Webb Space Telescope delayed again as costs rise," 27 June 2018 Managers said the main concern is that dust could temporarily cover its optical instruments. Washington Post, "NASA rover knocked out as gigantic dust storm envelops Mars," 13 June 2018 On the back there’s a 12MP wide-angle f/1.75 main lens paired with a 16MP telephoto one that delivers portrait mode and 2X optical zoom. Michael Simon, PCWorld, "HTC U12+ hands-on: No notch, smarter edges, and real selfie portraits," 23 May 2018 Police now have license-plate readers, which are mounted on squad cars and use optical-character-recognition technology to record license-plate numbers. Louis Menand, The New Yorker, "Why Do We Care So Much About Privacy?," 22 Sep. 2014 One room over, Wilson shows me the most impressive new toy in the group's digitization toolkit, one that arrived just three days earlier: A room-sized analog artifact known as an optical comparator. Adam Fisher, WIRED, "A Landmark Legal Shift Opens Pandora’s Box for DIY Guns," 10 July 2018 Frozen in place are more than 5,000 basketball-size optical sensors designed to catch a trace of a passing neutrino on the rare occasion one of them interacts with the ice. Robert Lee Hotz, WSJ, "Scientists Track Neutrinos Through Ice to Their Source in the Cosmos," 12 July 2018 Auerbach’s version is a wonder in the fireboat colors of red and white, filtered through her abstract and optical eye, combining painting with the laws of science into marbled swirls, liquid patterns, and blocks of color. Eve Macsweeney, Vogue, "There’s Plenty of Great Art to See (and Instagram) Outdoors in New York This Summer," 29 June 2018 The optical sensors also recognize traffic signs like speed limits and will display them prominently on the dash for you. Jonathan M. Gitlin, Ars Technica, "The 2018 Honda Accord proves there’s still life in the family sedan," 15 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'optical.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of optical

1570, in the meaning defined at sense 1

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Statistics for optical

Last Updated

8 Sep 2018

Look-up Popularity

Time Traveler for optical

The first known use of optical was in 1570

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English Language Learners Definition of optical

: used to help a person see

: relating to or using light

: involving the use of devices that get information for a computer by identifying patterns of light


op·ti·cal | \ˈäp-ti-kəl \

Kids Definition of optical

1 : relating to the science of optics

2 : relating to seeing : visual

3 : involving the use of devices that are sensitive to light to get information for a computer an optical scanner


op·ti·cal | \ˈäp-ti-kəl \

Medical Definition of optical 

1 : of or relating to the science of optics

2a : of or relating to vision : visual

b : using the properties of light to aid vision an optical instrument

3 : of, relating to, or utilizing light optical microscopy

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Comments on optical

What made you want to look up optical? Please tell us where you read or heard it (including the quote, if possible).


to reject or criticize sharply

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