Adj.

Definition: relating to or being a shadowy, indefinite, or marginal area

Ex. The penumbral lighting inside of the ruins gave the area an ominous air.

Adj.

Definition: of, causing, or being the partial shadow outside the complete shadow of an opaque body, such as a planet, where the light from the source of illumination is only partly cut off

Ex. Jamie had been excited about the coming eclipse until he leaned that it was penumbral and not total.