optical

adjective

op·​ti·​cal ˈäp-ti-kəl 

1

: of or relating to the science of optics

2

a

: 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

3

a

: 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

optically

ˈäp-ti-k(ə-)lē 

adverb

Synonyms

• ocular
• optic
• visual

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

Saturn won't be easily visible without a telescope and if using one care must be taken – daytime observations of any objects near the sun can be dangerous; accidentally pointing any optical aids at the sun while looking through them can result in permanent blindness. —Jesse Emspak, Space.com, 29 Jan. 2025

The industry wasn’t ready for a platform approach to optical connectivity. —Kyle J. Russell, USA TODAY, 25 Jan. 2025

These stones are not cubic zirconia, which is softer, less durable, and doesn't share the same optical properties as a diamond. —Garth Friesen, Forbes, 19 Jan. 2025

One shot in the trailer shows the Switch 2's Joy-Cons being dragged across a surface like a computer mouse, lending credence to rumors of them including an optical sensor. —Michael Gfoeller and David H. Rundell, Newsweek, 16 Jan. 2025

Word History

First Known Use

1570, in the meaning defined at sense 1

Phrases Containing optical

• electro-optical
• magneto-optical
• optical activity
• optical art
• optical bench
• optical disc
• optical fiber
• optical glass
• optical illusion
• optical rotation

Kids Definition

optical

adjective

op·​ti·​cal ˈäp-ti-kəl 

1

: relating to optics

2

: of or relating to vision

3

a

: of, relating to, or using light

an optical telescope

b

: involving the use of a device that senses light to acquire information for a computer

an optical scanner

optically

-k(ə-)lē 

adverb

Medical Definition

optical

adjective

op·​ti·​cal ˈäp-ti-kəl 

1

: of or relating to the science of optics

2

a

: 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