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 of optical

• 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

Previously considered an undesirable byproduct, these structures have displayed unusual optical properties, including the ability to polarize, refract, and conduct light in distinctive ways. — Kaif Shaikh, Interesting Engineering, 13 Oct. 2026

For health tracking, the Edge has an EKG sensor for atrial fibrillation detection, a skin temperature sensor, SpO2 and optical heart rate sensors, plus your typical motion tracking sensors. — Victoria Song, The Verge, 12 Oct. 2026

Constructed at the Amundsen-Scott South Pole Station starting in 1993, AMANDA was made up of 677 optical sensors deployed on 19 strings embedded deep in the polar ice. — Daniella McCahey, The Conversation, 12 Oct. 2026

Lumentum — Shares jumped 6% after the company's CEO Michael Hurlston said that Lumentum's optical components are sold out through 2029. — Davis Giangiulio, CNBC, 9 Oct. 2026

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 disk
• optical fiber
• optical glass
• optical illusion
• optical rotation

Rhymes for optical

• synoptical

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