Definitions
not transmitting or reflecting light or radiant energy; impenetrable to sight
Word origin
From Middle English opake, from Latin opacus (“shaded, shady, dark”) (of unknown origin), later reinforced from Middle French opaque. Doublet of ubac.
Used in a sentence
“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.”
“Through this opaque of Nature and of Soul, / This double night, transmit one pitying ray, / To lighten, and to cheer.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Not see-through”6 letters
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