Penumbra

(noun) Something that covers, surrounds, or obscures; surrounding region in which something exists in a lesser degree; In astronomy: partial shadow outside of completely shaded area, like in an eclipse or the outside of a sunspot. In painting: where light and shade blend.

Examples:

  1. June realized her colleague was working in a penumbra of immorality when he endorsed the product whose representatives afforded him the most appealing perks.
  2. Looking through the telescope, June saw the penumbra of light that surrounded it.
  3. A penumbra of heaviness set over the stadium as medics carried June from the field on a stretcher.