[ oh-peyk ]
See synonyms for: opaqueopaqueness on Thesaurus.com

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

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

  1. not shining or bright; dark; dull.

  2. hard to understand; not clear or lucid; obscure: The problem remains opaque despite explanations.

  3. dull, stupid, or unintelligent.

  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),o·paqued, o·paqu·ing.
  1. Photography. to cover up blemishes on (a negative), especially for making a printing plate.

  2. to cause to become opaque.

Origin of opaque

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

Other words for opaque

Other words from opaque

  • o·paque·ly, adverb
  • o·paque·ness, noun
  • sub·o·paque, adjective
  • sub·o·paque·ly, adverb
  • sub·o·paque·ness, noun

Words Nearby opaque

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use opaque in a sentence

British Dictionary definitions for opaque


/ (əʊˈpeɪk) /

  1. not transmitting light; not transparent or translucent

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

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

  2. hard to understand; unintelligible

  3. unintelligent; dense

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

verbopaques, opaquing or opaqued (tr)
  1. to make opaque

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

Origin of opaque

C15: from Latin opācus shady

Derived forms of opaque

  • opaquely, adverb
  • opaqueness, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for opaque


[ 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. Compare translucent transparent.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.