opaque

American  

[oh-peyk] / oʊˈpeɪk /

adjective

1. not transparent or translucent; impenetrable to light; not allowing light to pass through.

   Synonyms:

   muddy, cloudy, murky

2. not transmitting radiation, sound, heat, etc.

3. not shining or bright; dark; dull.

4. hard to understand; not clear or lucid; obscure.

   The problem remains opaque despite explanations.

5. dull, stupid, or unintelligent.

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noun

1. something that is opaque.

2. Photography. a coloring matter, usually black or red, used to render part of a negative opaque.

verb (used with object)

opaqued, opaquing

1. Photography. to cover up blemishes on (a negative), especially for making a printing plate.

2. to cause to become opaque.

opaque British  

/ əʊˈpeɪk /

adjective

1. not transmitting light; not transparent or translucent

2. not reflecting light; lacking lustre or shine; dull

3. not transmitting radiant energy, such as electromagnetic or corpuscular radiation, or sound

4. hard to understand; unintelligible

5. unintelligent; dense

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noun

1. photog an opaque pigment used to block out particular areas on a negative

verb

1. to make opaque

2. photog to block out particular areas, such as blemishes, on (a negative), using an opaque

opaque Scientific  

/ ō-pāk′ /

1. Resistant to the transmission of certain kinds of radiation, usually light. Metals and many minerals are opaque to light, while being transparent to radio waves and neutrinos.

2. Compare translucent transparent

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Other Word Forms

• opaquely adverb
• opaqueness noun
• subopaque adjective
• subopaquely adverb
• subopaqueness noun

Etymology

Origin of opaque

First recorded in 1375–1425; late Middle English opake, from Latin opācus “shaded”

Example Sentences

Sauté them quickly in the spiced fat until just opaque, then remove them before they turn rubbery.

From Salon • Apr. 7, 2026

A key issue is that many decisions are now made by automated or opaque systems.

From Science Daily • Apr. 5, 2026

Customers buy tokens to use AI services - but the amount of tokens needed for each task is sometimes opaque.

From BBC • Apr. 1, 2026

Mr. Ariosto also conducts informative interviews with Yao Song, a Chinese space entrepreneur, and Xue Suijian, a former high-ranking space official in the Chinese government, that provide glimpses into the opaque world of Chinese rocketry.

From The Wall Street Journal • Mar. 20, 2026

Red marble, its white veins illuminated in the light of the sun, which slowly vanished as the opaque glass doors groaned shut.

From "Throne of Glass" by Sarah J. Maas

Related Words

• blurred
• cloudy
• dirty
• dull
• frosty
• gloomy
• hazy
• impenetrable
• murky
• thick