Answer: penumbra

AnswerCrossword Clue
PENUMBRAShadow.
PENUMBRAShaded area of a sunspot.
PENUMBRAShadowy area
PENUMBRAVisual effect from a partial eclipse
penumbraa partial shadow
penumbraan area in which something exists to an uncertain degree.
penumbrathe partial shadow outside the complete shadow of a celestial body in eclipse