opaque
oh-PAYK
/oʊˈpeɪk/
Not permitting light to pass through; non-transparent; obscure or hard to comprehend.
Physically blocks light completely; metaphorically describes obscure writing or cryptic legal/financial reporting.
The story behind the word. Derived from Latin 'opacus', meaning 'in the shadow or dark'. It entered English in the 15th century to describe dense barriers, heavy drapes, and storm clouds.
Word relationships
- impervious: Impervious means impenetrable to liquids or radiation; opaque specifically means blocking light or understanding.
- obscure: Obscure emphasizes lack of clarity or fame, whereas opaque physically or structurally blocks light and insight.
- transparent: Transparent permits light and images to pass through clearly.
- translucent: Translucent allows light through while scattering detailed images.
Commonly confused with
- translucent: Opaque blocks all light; translucent passes diffused light softly.
Word family
- opacity (noun): The state or quality of being opaque.
Collocations
- opaque glass
- opaque language
- opaque decision-making
- opaque substance
Example sentences
- "Thick lead curtains are completely opaque, preventing dangerous X-rays from penetrating neighboring rooms." Material testing
- "Financial analysts complained that the holding company's opaque accounting methods concealed its true debt." Corporate critique
Memory hook
An O-PACKED wall is OPAQUE—no light gets through! Blocks light completely.
When not to use
Do not use for materials that allow blurred light through (use translucent).
Fun facts
- Human bones are opaque to visible light but partially translucent to high-energy X-rays.
Related words
Explore more words
transparent, obfuscate, cryptic, obstruct, obscurity, transparency
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