D defs.my
Entry 2 senses Webster, 1913

Opacity

/ōpăsʹĭti/ · O·pac·i·ty · IPA /oʊˈpæsɪti/
01 n. The state of being opaque; the quality of a body which renders it impervious to the rays of light; want of transparency; opaqueness.
  1. 1.
    The state of being opaque; the quality of a body which renders it impervious to the rays of light; want of transparency; opaqueness.
  2. 2.
    Obscurity; want of clearness.