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

The researchers then moved the cloud into a wider optical trap and gradually loosened its grip. — Atharva Gosavi, Interesting Engineering, 7 Nov. 2026

Sure, enthusiasts can add a larger LED light to illuminate scenes or an optical accessory viewfinder, but the Evo 2 doesn't work with external flashes. — Jim Fisher, PC Magazine, 5 Nov. 2026

Like its bigger siblings, the ELF-MN1 pairs an LCD with a micro-optical lens layer and a high-speed sensor that tracks your pupils. — New Atlas, 5 Nov. 2026

The optical assembly designed to record the distributions of iron ions in the corona is outfitted with astrocameras, each of which captures spectra from a different ionic species. — IEEE Spectrum, 5 Nov. 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