opaque

adj

1. Neither reflecting nor emitting light.

   “We have agreed that heat is energy to begin with. Light is also a form of energy for when absorbed by any opaque substance it turns completely into heat.”

2. Allowing little light to pass through, not translucent or transparent.
3. (figuratively)Unclear, unintelligible, hard to get or explain the meaning of.
4. (figuratively)Obtuse, stupid.
5. Describes a type for which higher-level callers have no knowledge of data values or their representations; all operations are carried out by the type's defined abstract operators.

noun

1. (obsolete, poetic)An area of darkness; a place or region with no light.

   “Through this opaque of Nature and of Soul, / This double night, transmit one pitying ray, / To lighten, and to cheer.”

2. Something which is opaque rather than translucent.

   “They can be obtained in various thicknesses and in many colors, including beautiful imitations of pearl, mother-of-pearl, veins and mottles, stratifications, roll stratifications, imitation corals, and all colors of translucents, transparents and opaques, grained ivory, shell (plain and corrugated mottle), onyx, wood effects, plaids, checks, stripes, metallic, bronze pearl plain, bronze pearl with fancy blocks, bronze pearl in veins and stripes, and what is called “essence pearl.””

verb

1. (transitive)To make, render (more) opaque.